# Dosyne — full text of the primary pages > Generated at build time from the rendered pages, so nothing here can disagree > with what a reader sees. This file carries the hubs, the API documentation and > the policy pages in full. The reference articles are long and each one has its > own markdown twin at /index.md; the data behind them is at > https://dosyne.com/api/v1/openapi.json. > Dosyne publishes arithmetic, not protocols. Nothing in this file is a dose > recommendation, and dosing decisions belong to a licensed prescriber. Index of the whole site: https://dosyne.com/llms.txt Generated: 2026-09-11 **Peptide Reconstitution Calculator & Dose Log | Dosyne** > Turn vial strength and bacteriostatic water into units on an insulin syringe, then keep the log. Free calculator in your browser, free app on iPhone and Android. Source: https://dosyne.com/ Peptide calculator · iPhone & Android # A unit is not a dose. Here is what your vial actually reads. The same 10 mg vial is 10 mg/mL in one millilitre of water and 5 mg/mL in two. The powder never changed — the syringe reading did. Dosyne does that arithmetic, shows the working, and keeps the concentration attached to every dose you log. [Get the app](https://dosyne.com/get/) Calculator free forever No account, no server Nothing leaves the device Reconstitution — live U-100 barrel · 1 unit = 0.01 mL Vial strength (mg) Bacteriostatic water (mL) Amount specified (mcg) Draw to — Volume — Concentration — Doses in the vial — Why this site exists ## Every page that explains this is published by somebody selling peptides. Search for a reconstitution calculator and the results are vendors, with one pharmacy chain and a couple of forum threads mixed in. That is not a conspiracy — it is just who had a reason to write the page. But it does mean the explanations stop precisely where the awkward parts begin, and the awkward parts are where the errors live. Error class 01 ### Units treated as a dose A unit on a U-100 barrel is 0.01 mL of liquid. It is a volume. The amount of substance it carries depends entirely on how much water went into the vial, so "draw 20 units" is meaningless without the concentration. This is the mistake that produces order-of-magnitude errors, and it is the one every chart on the internet quietly encourages. Error class 02 ### Charts with no concentration Most dosage charts print unit numbers without stating the concentration they assume. Applied to a vial mixed differently, they are wrong by whatever factor separates the two. We took this apart properly in [why most peptide dosage charts are unusable](https://dosyne.com/lab/peptide-dosage-charts/). Error class 03 ### Logs that stop making sense A tracker that records a milligram number and nothing else produces a history nobody can interpret once the vial changes. Six months later there is no way to tell what was actually administered. Storing the concentration with every entry is unglamorous and it is the thing that makes a log worth keeping. What we will not do ## We publish arithmetic. We do not publish protocols. You will not find a recommended dose anywhere on this site, or a suggested cycle, or a link to a vendor. Not because the topic is forbidden, but because those are the parts that require a prescriber who knows your history, and pretending otherwise would make everything else here less trustworthy. Stated plainly ### Most of these are not approved Most research peptides are not approved by the FDA or the EMA for human use. Material sold as research-use-only is not made to pharmaceutical standards simply because the label says so — purity, sterility, identity and actual content are not guaranteed, and a vial that dissolves clear can still be none of those things. Where evidence is thin ### We say the evidence is thin For most research peptides the published work is animal research, and the eight-week and twelve-week cycle conventions that circulate as pharmacology are largely forum consensus. Saying that is more useful than repeating it as fact, and it is what a page written by somebody with nothing to sell can afford to do. Where we are useful ### The arithmetic is genuinely safe ground Concentration, volume, unit conversion, syringe graduations, storage stability — these have correct answers, they are checkable, and getting them wrong is how people get hurt. So we are exhaustive about them, and that is the whole editorial position of the site. No commercial ties ### We sell no compounds and take no commission There are no vendor links here, no discount codes, no affiliate arrangements and no sponsored placements. Nothing on this site earns money if you buy anything anywhere. That is what lets us print the unflattering parts, and it is the reason the reference material is worth more than the pages that outrank it today. Evidence, honestly ### Where the science is thin, we say so For most research peptides the published work is animal research, and the cycle lengths circulating as established pharmacology are forum consensus. We report that rather than repeating confident numbers, and we mark clearly which statements are mechanism, which are convention and which are actually tested. Built for the record ### The log outlives your memory of it Six months later nobody remembers which vial a dose came from. Storing the concentration with every entry is the unglamorous decision that keeps a history interpretable, and it is what makes an export worth handing to a clinician instead of apologising for. In the app ## The calculator, and the record it feeds. The calculator is the reason people install it. The log is the reason they keep it. Every entry stores what was administered, at what concentration, on which date and at which site, so the history stays readable long after the details have left your memory. ![Dosyne Today screen listing due compounds with dose in micrograms and units, and remaining doses per vial](https://dosyne.com/img/screens/1-sm.webp) ![Dosyne reconstitution calculator converting vial strength and diluent volume into syringe units](https://dosyne.com/img/screens/2-sm.webp) ![Dosyne dose log history with dates and concentrations recorded](https://dosyne.com/img/screens/3-sm.webp) ![Dosyne injection site body map showing site rotation history](https://dosyne.com/img/screens/4-sm.webp) ![Dosyne progress chart with weight tracked over time](https://dosyne.com/img/screens/5-sm.webp) ![Dosyne compound library with reference information](https://dosyne.com/img/screens/6-sm.webp) Free, in your browser ## Five calculators, no sign-up, nothing transmitted. The same arithmetic that runs in the app, on the open web. Each one shows its working rather than returning an unexplained number, because a calculator you cannot check is a calculator you should not trust. [### Reconstitution calculator Vial strength and diluent volume to concentration, millilitres and units — with every intermediate number shown. Open the calculator →](https://dosyne.com/tools/peptide-reconstitution-calculator/)[### Bacteriostatic water calculator How much diluent to add to reach a concentration you can actually measure on the barrel you own. Open the calculator →](https://dosyne.com/tools/bacteriostatic-water-calculator/)[### Syringe visualizer A U-100 barrel drawn to scale, so you can hold your real syringe against the screen and compare. Open the calculator →](https://dosyne.com/tools/insulin-syringe-visualizer/)[### mcg to units converter The conversion nobody can do without a concentration, with the concentration made impossible to ignore. Open the calculator →](https://dosyne.com/tools/mcg-to-units-converter/)[### Titration planner Lay out the schedule your prescriber gave you as dates and syringe readings. It plans, it does not prescribe. Open the calculator →](https://dosyne.com/tools/glp1-titration-planner/) Pricing ## The calculator stays free. Pro is for the record-keeping. ### Free $0 forever - Reconstitution calculator, unlimited - Dose log with concentration stored per entry - Vial tracking and doses remaining - Bundled compound reference library ### Pro $49.99 per year, after a 7-day free trial · or $5.99 weekly - Dose reminders, cycle-aware - Cycle planner with phase tracking - Injection-site map with full rotation history - Weight progress, synced from Apple Health Cancel any time. The trial costs nothing. Questions ## Straight answers. Is Dosyne free? The reconstitution calculator is free forever, along with the dose log and vial tracking. Pro adds reminders, the cycle planner, the injection-site map history and weight progress with Apple Health — $5.99 a week or $49.99 a year with a 7-day free trial. The calculator is never paywalled, because it is the part people need most often. Does Dosyne tell me what dose to take? No, and it never will. Dosyne converts numbers you already have into a syringe reading: vial strength, diluent volume and the amount specified by your prescriber become millilitres and units. What to use, how much and how often is a decision for a licensed prescriber, and no calculator can make it. What is a unit on an insulin syringe? On a U-100 syringe, one unit is a volume of 0.01 mL. It is not a quantity of drug. Ten units is 0.10 mL whether the barrel contains insulin, saline or a reconstituted peptide, and how much substance that carries depends entirely on the concentration in the vial. Confusing the two is the single most common error in this subject. How much bacteriostatic water should I add? There is no single correct volume. The amount you add sets the concentration, which sets the syringe reading, so the practical approach is to work backwards from a reading you can measure accurately. The free bacteriostatic water calculator on this site does that arithmetic and shows every step. Does my data leave the phone? No. There is no account, no login and no server. Your logs, vials and settings are stored on the device, all calculations run locally, and the app has no analytics SDK of any kind. The App Store privacy label says Data Not Collected because that is genuinely true. Does it work for GLP-1 medications? The arithmetic is the same for any reconstituted vial, so semaglutide and tirzepatide work exactly like anything else: read the concentration on the vial, enter the amount your prescriber specified, and get the syringe reading. Dosyne also records which dose you took and when, which is what a prescriber uses to decide the next titration step. Can I keep using it after a vial changes? Yes, and this is the specific thing most trackers get wrong. Dosyne stores the concentration alongside every logged dose, so a history stays interpretable months later even after the vial strength or the diluent volume changed. A log of milligram numbers with no concentration attached becomes unreadable the moment anything changes. Is it on Android? Yes, on Google Play as well as the App Store. The free calculators on this website work in any browser on any device if you would rather not install anything at all. The Lab ## The reference we could not find anywhere else. Reconstitution arithmetic, syringe graduations, storage chemistry and the honest state of the evidence. [Read the whole section](https://dosyne.com/lab/). [Jul 30, 2026 ### Peptide tracker app: what it actually needs to do Peptide tracker app comparison: which apps keep the concentration attached to every logged dose, survive a vial change, and export a history a clinician can read.](https://dosyne.com/lab/peptide-tracker-apps/)[Jul 28, 2026 ### Peptide reconstitution mistakes: nine ways to quietly ruin a vial Peptide reconstitution mistakes can ruin a vial or distort a dose. Learn the failure modes, concentration math, syringe errors, and discard signals.](https://dosyne.com/lab/reconstitution-mistakes/)[Jul 26, 2026 ### Subcutaneous injection site rotation that holds up Subcutaneous injection site rotation protects usable tissue and reduces absorption variability. Learn how to map zones, spot lipohypertrophy, and log sites.](https://dosyne.com/lab/injection-site-rotation/) ## Do the arithmetic once, keep the record forever. Free on iPhone and Android. No account, no server, nothing leaves your phone. [Get the app](https://dosyne.com/get/) Free · no account · nothing leaves your phone --- HTML version: https://dosyne.com/ Structured data for this site: https://dosyne.com/api/v1/openapi.json · https://dosyne.com/llms.txt Dosyne publishes arithmetic, not protocols: nothing here is a dose recommendation, and dosing decisions belong to a licensed prescriber. Free to quote and reuse with a link back to the source URL above (CC BY 4.0). --- **Free peptide calculators: formulas, units, and checks | Dosyne** > Free peptide calculators for reconstitution, concentration, syringe units, and mcg conversion, with formulas and checks for auditing each result. Source: https://dosyne.com/tools/ [Home](https://dosyne.com/)/Free tools Free tools · no sign-up # Free peptide calculators: five tools and the arithmetic Free peptide calculators for reconstitution, concentration, syringe units, and mcg conversion, with formulas and checks for auditing each result. [Mixing a vial **Reconstitution calculator** Vial strength and diluent volume to concentration, millilitres and units, with every step shown.](https://dosyne.com/tools/peptide-reconstitution-calculator/)[Deciding the water **Bacteriostatic water calculator** How much diluent to add to reach a concentration you can measure on the barrel you own.](https://dosyne.com/tools/bacteriostatic-water-calculator/)[Reading the barrel **Insulin syringe visualizer** A U-100 barrel drawn to scale, so you can hold your syringe against the screen and compare.](https://dosyne.com/tools/insulin-syringe-visualizer/)[Checking a chart **mcg to units converter** The conversion that is impossible without a concentration, with the concentration made impossible to ignore.](https://dosyne.com/tools/mcg-to-units-converter/)[Following a plan **GLP-1 titration planner** Lay out the schedule you were given as dates and syringe readings. It plans; it never prescribes.](https://dosyne.com/tools/glp1-titration-planner/) A 10 mg vial reconstituted with 2 mL contains 5 mg/mL. On a U-100 insulin syringe, that stated concentration corresponds to 50 mcg per unit. Those two lines are the useful center of peptide arithmetic: divide the amount by the liquid, convert units deliberately, and keep the syringe scale separate from the compound itself. This page collects five free peptide calculators for five different decisions. One answers how a vial becomes a concentration. One checks how a selected diluent volume affects the result. One shows where a volume sits on a syringe. One converts an amount in micrograms to U-100 units. One lays out dates and intervals as a planning worksheet, not as a prescription. The tools are deliberately narrow because narrow tools are easier to audit. Dosyne is built around the same principle. Its calculator and dose log keep the working visible on the device rather than asking the user to trust an unexplained result or send personal records to a server. The arithmetic still deserves independent checking. Software can make division less tedious; it cannot make an unknown vial known. ## Choose the calculator by the decision ### Need to know the concentration after adding liquid Use the [Peptide reconstitution calculator](https://dosyne.com/tools/peptide-reconstitution-calculator/) when the question is: “What concentration will this vial have after this volume of diluent is added?” It supports the first calculation in the chain. Enter the vial strength and the relevant liquid volume, then read the resulting mg/mL or mcg/mL. That result is not an amount selected for administration. It is a property of the mixture. If the vial contains 5 mg and the working volume is 1 mL, the concentration is 5 mg/mL. If the same vial has a working volume of 2 mL, the concentration is 2.5 mg/mL. Nothing about the peptide amount changed; the amount of liquid did. The phrase “working volume” matters. A stated volume added to a dry powder may not be identical to the final volume of the resulting solution because the powder and the liquid occupy space. For a simple arithmetic check, the stated final volume is the correct denominator. If product documentation distinguishes between volume added and final volume, use the documented value consistently and do not mix the two. ### Need to examine the diluent and final concentration Use the [Bacteriostatic water calculator](https://dosyne.com/tools/bacteriostatic-water-calculator/) when the calculation concerns how a selected liquid volume affects concentration and draw volume. “Bacteriostatic” describes the water’s preservative system, not a guarantee that it is suitable for every peptide, vial, route, or storage period. Bacteriostatic water commonly contains benzyl alcohol as a preservative. That fact does not answer compatibility, sterility after repeated access, or stability. The product labeling and a qualified clinician or pharmacist control those questions. The calculator handles the division. A diluent calculator also cannot tell whether a particular dry material should be exposed to a particular pH, preservative, salt concentration, or solvent. Two liquids can both appear clear while having different effects on solubility or chemical stability. A clear solution is not laboratory evidence of identity, purity, or sterility. ### Need to see the physical syringe position Use the [Insulin syringe unit visualizer](https://dosyne.com/tools/insulin-syringe-visualizer/) when the calculation is complete and the remaining question is where the volume sits on the syringe in hand. A numerical answer such as 7 units is not the same thing as a visible mark unless the syringe has the expected scale and graduations. Most familiar insulin syringes use U-100 calibration, but “insulin syringe” does not by itself prove the scale. Read the barrel. A syringe marked in units for another concentration, or a tuberculin syringe marked directly in mL, needs a different conversion. Never transfer a U-100 result to a different scale without recalculating. The visualizer is most useful for detecting scale mismatch and small-volume problems. It cannot determine whether a line is easy to read under actual lighting, whether the plunger is aligned consistently, or how much liquid remains in the hub. Those are measurement limitations, not failures of the formula. ### Need to translate micrograms into U-100 units Use the [mcg to units converter](https://dosyne.com/tools/mcg-to-units-converter/) when the specified amount is expressed in micrograms but the syringe is read in units. This is a two-step conversion disguised as one button: amount divided by concentration gives milliliters; milliliters multiplied by 100 gives U-100 units. The converter cannot infer the vial concentration. That value must come from the actual reconstitution calculation or verified product documentation. A result based on 5 mg/mL is wrong if the working concentration is 2.5 mg/mL, even if the button press was flawless. “Units” is not a mass unit. It is a volume-related marking tied to a particular calibration. The same number of U-100 units can represent different amounts of peptide at different concentrations. Conversely, the same mass amount can occupy different syringe positions after different reconstitution calculations. ### Need to inspect a proposed schedule as a calendar problem Use the [GLP-1 titration schedule planner](https://dosyne.com/tools/glp1-titration-planner/) when the question concerns dates, intervals, and a written sequence that needs to be reviewed with a prescriber. It is a planning aid, not an instruction to start, increase, maintain, or stop a medication. It does not turn a research peptide into an approved product, and it does not replace an individualized clinical plan. Titration is pharmacology, not just arithmetic. The amount present in the body changes over time according to absorption, distribution, metabolism, elimination, and the compound’s half-life. A calendar can show spacing; it cannot predict an individual response or settle whether a schedule is appropriate. A schedule planner also should not be mistaken for a pharmacokinetic simulator. A calendar can mark seven-day or fourteen-day intervals, but it cannot establish steady state, account for delayed absorption, model missed administrations, or predict concentrations in a particular person. Those questions require compound-specific evidence and clinical judgment. ## The arithmetic every tool uses The formulas below are enough to reproduce every concentration, volume, and U-100 unit result with a pen. Keep the units written beside each number. Most mistakes are unit mistakes wearing a confident expression. ### 1. Calculate concentration The basic concentration formula is: `concentration = amount in vial ÷ final liquid volume` If the vial contains 10 mg and the final liquid volume is 2 mL: `10 mg ÷ 2 mL = 5 mg/mL` The final volume matters. If the powder displaces some liquid, the nominal amount added may not equal the final volume. For a basic calculation, use the stated working or final volume supplied by the applicable instructions. If documentation gives a different final-volume instruction, use that stated value rather than inventing a correction. To convert mg/mL to mcg/mL, multiply by 1,000: `5 mg/mL × 1,000 mcg/mg = 5,000 mcg/mL` To convert mcg/mL to mg/mL, divide by 1,000: `5,000 mcg/mL ÷ 1,000 mcg/mg = 5 mg/mL` Do not skip this step because “mg” and “mcg” differ by three orders of magnitude. A misplaced zero is not a minor rounding error. Dimensional analysis exposes the correct direction: multiplying mg by `1,000 mcg/mg` cancels mg and leaves mcg. A useful equivalent formula is: `mcg per 0.01 mL = mcg/mL × 0.01 mL` At 5,000 mcg/mL: `5,000 mcg/mL × 0.01 mL = 50 mcg` That is the amount represented by one U-100 unit at this concentration. The number changes if either the concentration or the syringe calibration changes. ### 2. Calculate draw volume Once concentration and the specified amount use the same mass unit, calculate volume as: `draw volume = specified amount ÷ concentration` For a hypothetical specified amount of 250 mcg at 5,000 mcg/mL: `250 mcg ÷ 5,000 mcg/mL = 0.05 mL` The same calculation in milligrams is possible: `0.25 mg ÷ 5 mg/mL = 0.05 mL` The two answers agree because 250 mcg equals 0.25 mg. If the specified amount is in mcg and concentration is in mg/mL, convert one before dividing. Do not divide 250 by 5 and call the result milliliters. The units expose the error. The formula can also be rearranged: `specified amount = concentration × volume` That rearranged form is useful for a reverse check. If a calculator reports 0.05 mL at 5,000 mcg/mL, multiply them: `5,000 mcg/mL × 0.05 mL = 250 mcg` The mL units cancel, returning the specified amount. If they do not cancel, the input units are not aligned. ### 3. Convert milliliters to U-100 units U-100 means 100 units per milliliter. Therefore: `1 U-100 unit = 0.01 mL` The conversions are: `units = mL × 100` `mL = units ÷ 100` For 0.05 mL: `0.05 mL × 100 units/mL = 5 units` For a direct mcg-to-units calculation, combine the formulas. First find the mcg per unit: `mcg per unit = mcg/mL ÷ 100 units/mL` At 5,000 mcg/mL: `5,000 mcg/mL ÷ 100 units/mL = 50 mcg/unit` Then: `units = specified mcg ÷ mcg per unit` For 250 mcg: `250 mcg ÷ 50 mcg/unit = 5 units` The combined formula is: `U-100 units = specified mcg × 100 ÷ concentration in mcg/mL` That formula applies only to a U-100 syringe. The “100” is not a property of the peptide. It belongs to the syringe calibration. For a syringe marked in mL rather than units, stop at the draw-volume result. Do not multiply by 100 unless the barrel is actually calibrated U-100. For a different unit calibration, substitute that calibration into the formula: `units on that syringe = mL × units per mL` The label’s units-per-mL value must be known before using that version of the formula. ### 4. Account for syringe graduations A calculated volume can be mathematically correct but impractical to read. The smallest graduation varies by syringe, and the barrel may be difficult to read at low volumes. A 0.03 mL result is 3 U-100 units, but whether a person can measure that consistently depends on the syringe design, graduation interval, lighting, and technique. Do not round early. Carry extra decimal places through the calculation, then compare the final result with the syringe’s graduations. If a result must be rounded for measurement, the rounded amount is a different amount. That difference should be reviewed with the prescriber rather than silently treated as equivalent. For example, if the calculated result is 3.7 U-100 units and the syringe has 1-unit graduations, the barrel may display a position between marked lines. Rounding to 4 units changes the represented volume from 0.037 mL to 0.04 mL. At a concentration of 5,000 mcg/mL, that difference represents 15 mcg. The calculator should show the unrounded arithmetic; the measurement decision is separate. Graduation spacing is not the same as claimed accuracy. A barrel with half-unit marks may permit finer positioning than a barrel with 1-unit marks, but it does not prove that the delivered amount is exact to half a unit. Manufacturing tolerances, plunger fit, reading angle, and retained liquid still matter. Dead space adds another complication. Dead space is the liquid retained in the needle hub and syringe after the plunger reaches its endpoint. It can make the amount delivered differ from the amount calculated from barrel markings, particularly at small volumes. Low-dead-space syringes reduce retained volume; they do not remove the need to check the scale and technique. ### 5. Keep the order of operations visible A complete worked example looks like this: - Vial: 15 mg - Working liquid volume: 3 mL - Concentration: `15 mg ÷ 3 mL = 5 mg/mL` - Converted concentration: `5 × 1,000 = 5,000 mcg/mL` - One U-100 unit: `5,000 ÷ 100 = 50 mcg/unit` - Volume for any stated amount: `specified mcg ÷ 5,000 mcg/mL` - U-100 units for any stated amount: `specified mcg ÷ 50 mcg/unit` This is the entire chain. The calculators package it, store it, or display it visually. They do not add a clinical conclusion at the end. ### 6. Calculate dilution factor without losing the original amount A dilution changes concentration, not the total amount of material assumed to be present. If a 10 mg amount is represented in 1 mL, the concentration is 10 mg/mL. If the working volume becomes 2 mL while the amount remains 10 mg, the concentration becomes 5 mg/mL. The concentration has been reduced by a factor of two. The dilution factor can be written as: `dilution factor = new volume ÷ original volume` For 1 mL to 2 mL: `2 mL ÷ 1 mL = 2` The new concentration is the original concentration divided by that factor: `10 mg/mL ÷ 2 = 5 mg/mL` This shortcut is valid only when the amount of peptide remains unchanged and the volumes refer to comparable working volumes. It does not correct for degradation, adsorption to the container, incomplete dissolution, or a mislabeled starting amount. ### 7. Check percentage and decimal notation A calculator may display `0.05 mL`, `50 microliters`, or `5 U-100 units` for the same volume. The conversions are: `1 mL = 1,000 microliters` `0.05 mL × 1,000 microliters/mL = 50 microliters` `0.05 mL × 100 U-100 units/mL = 5 U-100 units` These are three descriptions of volume, not three different amounts of peptide. A result written as `0.5 mL` is ten times `0.05 mL`; a missing zero changes the arithmetic by a factor of ten. Entering a decimal with a leading zero makes the intended value easier to read and harder to misinterpret. ## Reference table: vial strength, liquid volume, and unit value The table assumes the listed liquid volume is the working final volume and the syringe is U-100. “One unit carries” means the amount in 0.01 mL, not a recommended amount to draw. | Vial amount | Working liquid volume | Resulting concentration | One U-100 unit carries | | --- | --- | --- | --- | | 5 mg | 1 mL | 5 mg/mL (5,000 mcg/mL) | 50 mcg | | 5 mg | 2 mL | 2.5 mg/mL (2,500 mcg/mL) | 25 mcg | | 10 mg | 1 mL | 10 mg/mL (10,000 mcg/mL) | 100 mcg | | 10 mg | 2 mL | 5 mg/mL (5,000 mcg/mL) | 50 mcg | | 10 mg | 4 mL | 2.5 mg/mL (2,500 mcg/mL) | 25 mcg | | 15 mg | 3 mL | 5 mg/mL (5,000 mcg/mL) | 50 mcg | | 20 mg | 2 mL | 10 mg/mL (10,000 mcg/mL) | 100 mcg | | 30 mg | 3 mL | 10 mg/mL (10,000 mcg/mL) | 100 mcg | | 50 mg | 5 mL | 10 mg/mL (10,000 mcg/mL) | 100 mcg | The table demonstrates why “units” alone are incomplete. Five units from the 5 mg/mL rows carries 250 mcg. Five units from the 10 mg/mL rows carries 500 mcg. The syringe reading stayed the same; the concentration did not. The table also shows why a vial label alone is insufficient for a volume calculation. A 10 mg vial can produce 10 mg/mL, 5 mg/mL, or 2.5 mg/mL in the rows above. The vial amount supplies the numerator, but the liquid volume supplies the denominator. ## Storage stability: what can and cannot be calculated Arithmetic can calculate concentration after preparation. It cannot calculate how long that concentration remains accurate or sterile. Stability depends on the compound, formulation, pH, excipients, container, closure, temperature history, light exposure, agitation, freeze-thaw events, and the quality of the original material. A temperature conversion is not a stability assessment. For example: `37°F = (37 − 32) × 5/9 = 2.8°C` That conversion tells you the equivalent temperature. It does not establish that a peptide remains stable at 2.8°C for a particular period. A refrigerator reading also does not describe excursions during transport, time at room temperature, exposure to light, or repeated access to the vial. A simple storage log can still preserve useful facts. Record the date and time of preparation, the stated liquid volume, the storage temperature range if measured, exposure to light or freezing, and any visible change. Those entries document handling history; they do not certify potency or sterility. “Refrigerated” does not mean indefinitely stable, and a preserved diluent does not preserve a peptide forever. Do not infer a beyond-use date from the concentration, the vial size, or the presence of benzyl alcohol. Use applicable product, pharmacy, or manufacturer instructions. If no reliable instructions exist for the material, the uncertainty cannot be solved with a calculator. ## What the arithmetic cannot tell you A calculator can check a relationship among numbers. It cannot check identity, purity, potency, sterility, endotoxin contamination, particulate matter, degradation, labeling accuracy, or whether the material should be administered. It cannot inspect the vial, test a batch, or detect a cold-chain failure. Most research peptides are not approved by the FDA or EMA for human use. Material sold as “research use only” is not manufactured to pharmaceutical standards, and its purity, sterility, and actual content are not guaranteed. Human evidence is thin or absent for many such compounds, including several commonly discussed online. Mechanistic plausibility is not clinical evidence. This distinction matters for familiar names as well as obscure ones. Semaglutide and tirzepatide have approved medical uses in specific products and indications, but that fact does not authenticate an unapproved preparation bearing either name. BPC-157 and retatrutide illustrate a different problem: public discussion can move faster than reliable human evidence and regulatory review. A calculator also cannot detect a concentration error caused by an incorrect label. If a container states 10 mg but contains a different amount, the result from `10 mg ÷ 2 mL` is mathematically correct for the label and factually wrong for the material. The same limitation applies to an incorrect liquid volume, a syringe with a different calibration, or a transcription error copied into an app. The clinical decision belongs to a licensed prescriber. The tools are for checking the math around an established instruction, not for selecting a compound or creating a protocol from internet fragments. ## Glossary ### Reconstitution Reconstitution is adding a liquid to a dry material, often a lyophilized powder, to create a solution or suspension. The amount of liquid changes the concentration. Reconstitution is not the same as dilution, although ordinary discussion often uses the terms loosely. ### Diluent A diluent is the liquid used to dissolve or dilute another material. Its ingredients, preservative system, pH, sterility, and compatibility matter. “Water” is not a complete specification. ### Bacteriostatic water Bacteriostatic water is sterile water containing a preservative intended to inhibit bacterial growth in the container under labeled conditions. It is not a universal solvent, does not make contaminated material safe, and does not eliminate contamination risk after repeated access. ### Concentration Concentration is the amount of material per unit of volume, such as mg/mL or mcg/mL. It describes the mixture. It is not the same as the amount selected for administration. ### U-100 U-100 is a syringe calibration meaning 100 insulin units per mL. For arithmetic, one U-100 unit equals 0.01 mL. It does not mean that every injectable liquid has the same amount per unit. ### Syringe graduation A graduation is a marked interval on a syringe barrel. Its value depends on the syringe’s calibration and scale. The smallest visible interval limits how finely a volume can be read; it does not guarantee equivalent delivery accuracy. ### Dead space Dead space is the volume retained inside a syringe or needle hub that does not reach the intended destination. It affects delivered volume and can matter more as the measured volume gets smaller. ### Lyophilized Lyophilized means freeze-dried. Removing water can improve storage characteristics for some formulations, but it does not establish stability after reconstitution. A lyophilized vial still requires appropriate instructions for solvent, handling, and storage. ### Half-life Half-life is the time required for the amount or concentration of a substance in a defined system to fall by half under specified conditions. It is a pharmacokinetic property, not a dosing interval, storage period, or measure of product quality. ## A practical checking routine Write down the vial amount exactly as labeled. Write down the liquid volume and whether it is an amount added or a stated final volume. Calculate mg/mL, convert to mcg/mL if the specified amount uses micrograms, calculate mcg per U-100 unit, and only then calculate the syringe units. Next, perform a reverse check. Multiply the displayed units by 0.01 mL per unit, then multiply the resulting volume by mcg/mL. If the answer does not return the intended amount, the input, conversion, or syringe assumption is wrong. This reverse check takes less time than arguing with a decimal later. For a U-100 result, the complete reverse check is: `units ÷ 100 = mL` `mL × mcg/mL = mcg represented` For example, 5 units becomes 0.05 mL. At 5,000 mcg/mL: `0.05 mL × 5,000 mcg/mL = 250 mcg` Finally, compare the result with the physical syringe. Confirm U-100 marking, inspect the graduation interval, and consider dead space. Dosyne can keep the vial and dose history together on the phone, but the written calculation remains the clearest audit trail when the numbers matter. If the result changes after correcting a unit, volume, or calibration entry, preserve both versions in the record rather than overwriting the original calculation. A visible correction makes it easier to identify how an error occurred and prevents a later reader from mistaking the first result for the verified one. For readers comparing calculation and tracking approaches rather than arithmetic alone, [How the peptide trackers actually differ](https://dosyne.com/compare/) is the relevant comparison. The broader [The Lab — reconstitution arithmetic, written by people with nothing to sell](https://dosyne.com/lab/) keeps the same boundary: explain what can be calculated, identify what cannot, and do not manufacture certainty. If a private, on-device record is the practical requirement, search for “Dosyne Peptide Calc & Tracker” in the App Store or Google Play. That tells you where to find the app; it does not change what a calculator can know. ## Bottom line The best free peptide calculator is the one that exposes its working and uses the correct syringe scale. Start with concentration, convert mg to mcg deliberately, calculate volume, convert volume to U-100 units only when U-100 is actually printed on the syringe, and reverse-check the result. Use the tools to audit arithmetic, not to validate a product or invent a dosing plan. Numbers can be exact while the underlying vial remains unknown. ## Frequently asked questions What is the formula for peptide reconstitution? Concentration equals the amount of peptide in the vial divided by the final liquid volume. For example, 10 mg in 2 mL produces 5 mg/mL, or 5,000 mcg/mL. The volume corresponding to a specified amount equals that amount divided by the concentration. A calculator checks this arithmetic; it cannot verify the vial’s contents, sterility, or suitability for administration. How many units are in 1 mL on a U-100 insulin syringe? A U-100 insulin syringe is calibrated for 100 units per mL, so 1 mL equals 100 units and 0.01 mL equals 1 unit. The conversion is units = mL × 100, and mL = units ÷ 100. This applies only to a U-100 syringe. A different syringe scale requires a different conversion. How do I convert mcg to insulin syringe units? First calculate the concentration in mcg/mL. Then calculate the volume by dividing the specified amount in mcg by the concentration in mcg/mL. For a U-100 syringe, multiply that volume by 100 to get units. Equivalently, U-100 units = desired mcg × 100 ÷ concentration in mcg/mL. The result changes whenever the vial strength or liquid volume changes. How much bacteriostatic water should be added to a peptide vial? There is no universal volume. The appropriate liquid, amount, final concentration, compatibility, and handling instructions depend on the specific product and preparation. Adding more liquid lowers concentration; adding less raises it. Bacteriostatic water contains a preservative and is not automatically appropriate for every compound or container. A licensed prescriber or pharmacist must determine preparation instructions. Are free peptide calculators accurate? A calculator can perform accurate arithmetic when the vial amount, final liquid volume, unit system, and specified amount are entered correctly. It cannot correct a mislabeled vial, an incorrect syringe scale, a measuring error, degradation, contamination, or unknown peptide content. The result is arithmetic, not proof that a research product is authentic, sterile, safe, or appropriate to use. Can I use an online reconstitution calculator for research peptides? An online calculator can check concentration and volume arithmetic if the entered values are verified and the formulas are understood. It cannot test the material or establish a safe preparation method. Most research peptides are not approved by the FDA or EMA for human use, and products labeled research use only are not manufactured to pharmaceutical standards. Purity, sterility, and actual content are not guaranteed. What does 10 mg in 2 mL equal on a U-100 syringe? Ten milligrams divided by 2 mL equals 5 mg/mL, or 5,000 mcg/mL. One U-100 unit is 0.01 mL, so one unit contains 50 mcg at that stated concentration. For any specified amount, divide the amount in mcg by 50 mcg per unit to calculate the corresponding U-100 units. The arithmetic does not establish that the material should be administered. What is the difference between peptide concentration and dose? Concentration describes how much material is present in a volume, such as 5 mg/mL. A dose is the amount selected for administration, expressed in units such as mcg or mg. The volume connects them: volume equals specified amount divided by concentration. Concentration describes the prepared mixture; selecting an amount for administration is a separate clinical decision. ### The same arithmetic, in your pocket Dosyne keeps the concentration attached to every logged dose, so a history stays readable months later. Free on iPhone and Android, no account. [Get the app](https://dosyne.com/get/) Free · no account · nothing leaves your phone --- HTML version: https://dosyne.com/tools/ Structured data for this site: https://dosyne.com/api/v1/openapi.json · https://dosyne.com/llms.txt Dosyne publishes arithmetic, not protocols: nothing here is a dose recommendation, and dosing decisions belong to a licensed prescriber. Free to quote and reuse with a link back to the source URL above (CC BY 4.0). --- **Peptide Reconstitution Guide | The Lab | Dosyne** > Peptide reconstitution guide for checking concentration, volume, syringe units, unit conversions, storage records, and incomplete research-peptide charts. Source: https://dosyne.com/lab/ · updated: 2026-07-30 [Home](https://dosyne.com/)/The Lab The Lab # Peptide reconstitution guide Peptide reconstitution guide for checking concentration, volume, syringe units, unit conversions, storage records, and incomplete research-peptide charts. A 5 mg vial mixed with 2 mL of diluent contains 2.5 mg/mL. On a U-100 syringe, 10 units is 0.10 mL. That volume contains 0.25 mg, or 250 mcg, at that concentration. Change the diluent volume to 1 mL and the same 10 syringe units contain 0.5 mg. The syringe did not change. The concentration did. That is the subject in miniature: arithmetic that is simple enough to do on paper, with enough opportunities for a missing label, a copied chart, or a unit error to make the result wrong. Reconstitution should be treated as a recordable calculation, not as a ritual and not as a substitute for verified product instructions. Most pages ranking for peptide arithmetic are published by people selling peptides, testing services, subscriptions, or a combination of them. That does not establish that every explanation is wrong. It does mean a reader should inspect the assumptions. A neat syringe diagram is incomplete if it omits the concentration, syringe scale, vial strength, and diluent volume that make its units meaningful. “Research use only” is also not a quality certificate. ## The four facts required before a number means anything A volume drawn from a syringe is not a peptide amount by itself. To interpret it, four facts must sit beside it in the record: vial strength, diluent volume, resulting concentration, and syringe type. Omit any one of them and the calculation becomes partial evidence presented as an answer. A fifth record field is useful in practice: the date and identity of the vial or preparation. It does not alter the equation, but it prevents a correct calculation from being attached to the wrong container later. ### 1. Vial strength Vial strength is the total amount of peptide in the container, usually stated in milligrams or micrograms. “5 mg vial” describes the amount supplied, not the amount in a syringe and not the concentration after mixing. Strength gets missed because labels and informal charts use shorthand. A label may say 5 mg while a message says “the 5,” and a log may record only the compound name. If the same compound is later supplied in 10 mg or 15 mg strength, old unit instructions no longer transfer automatically. Write the amount and unit exactly. If the label says 5 mg, retain 5 mg until the conversion requires micrograms. Since 1 mg equals 1,000 mcg, 0.25 mg equals 250 mcg. Keep the unit attached to every intermediate value. A bare number such as “0.25” is not a usable record because it could mean milligrams, milliliters, or syringe units. Do not infer vial strength from the total powder mass, the vial size, or the amount of liquid that fits in the container. A 3 mL vial is a container specification, not a statement that it holds 3 mL of liquid or a particular mass of peptide. ### 2. Diluent volume Diluent volume is the amount of liquid added to the vial. It is measured in milliliters. It is not a cosmetic detail and it does not disappear from the calculation after mixing. For the illustrative 5 mg vial: - Add 1 mL: 5 mg ÷ 1 mL = 5 mg/mL. - Add 2 mL: 5 mg ÷ 2 mL = 2.5 mg/mL. - Add 2.5 mL: 5 mg ÷ 2.5 mL = 2 mg/mL. Those are three different concentrations from the same vial. A chart that states only “10 units” has not supplied enough information to reproduce its result. People also confuse the vial’s nominal capacity with the volume added. Powder displacement, transfer loss, and liquid remaining in a syringe can affect the actual volume. A calculator can use the stated inputs; it cannot inspect the vial and recover an unknown volume. The volume shown on a syringe is also a measurement with limited resolution. If a syringe is marked in 0.01 mL increments, a value between those marks is an estimate rather than a more precise laboratory measurement. Do not report extra decimal places simply because a calculator displays them. ### 3. Resulting concentration Concentration connects the vial to the syringe. The basic equation is: `concentration = total peptide amount ÷ total liquid volume` Then: `peptide amount in a drawn volume = concentration × drawn volume` Using 5 mg in 2 mL gives 2.5 mg/mL. A 0.10 mL draw contains: `2.5 mg/mL × 0.10 mL = 0.25 mg` The milliliters cancel, leaving milligrams. That cancellation is a useful check. If the final line still says mg/mL when you are trying to calculate the amount in a syringe, the working is unfinished. Concentration is frequently missed because people record the vial strength and syringe units but not the mixture that connects them. A vial log should preserve the original strength, the diluent volume, the date of preparation, and the calculated concentration as one entry. The vial and calculation remain attached instead of becoming a loose number in a note. A concentration can also be written in micrograms per milliliter. The same 2.5 mg/mL is 2,500 mcg/mL. That conversion is valid because 1 mg equals 1,000 mcg; it does not change the liquid volume. Choose one mass unit for the calculation and keep it consistent until the final conversion. The [Peptide reconstitution calculator](https://dosyne.com/tools/peptide-reconstitution-calculator/) is useful for checking this arithmetic. Its result is only as sound as the values entered. A calculator does not turn an unknown concentration into a known one. ### 4. Syringe type “Syringe units” are a scale, not a universal mass measurement. A standard U-100 insulin syringe is marked so that 100 units equal 1 mL. Therefore: | Syringe scale | 1 mL equals | 10 units equals | Conversion rule | | --- | --- | --- | --- | | U-100 | 100 units | 0.10 mL | mL = units ÷ 100 | | U-40 | 40 units | 0.25 mL | mL = units ÷ 40 | | Tuberculin syringe | Usually marked in mL | Not a universal unit scale | Read the mL graduations | The table is a reference, not a reason to assume a syringe type. Confirm the marking printed on the barrel. A U-100 syringe and a U-40 syringe can both show “10,” while representing different volumes. Graduation size also matters. A nominal 0.3 mL syringe may have markings that permit finer or coarser reading than another syringe. Dead space can alter the amount retained in the needle and hub, particularly at small volumes. That affects delivery and waste; it does not change the printed unit conversion. A syringe marked in insulin units is not interchangeable with a syringe marked in milliliters simply because both can hold liquid. A 0.10 mL reading on a tuberculin syringe corresponds to 10 units on a U-100 scale, but the tuberculin syringe does not become a U-100 syringe. Record the scale actually printed on the device. The [Insulin syringe unit visualizer](https://dosyne.com/tools/insulin-syringe-visualizer/) helps translate the scale into milliliters. For conversions that cross mass units, the [mcg to units converter](https://dosyne.com/tools/mcg-to-units-converter/) shows the intermediate concentration instead of hiding it. ## The unit ladder: mg, mcg, mL, and syringe units Four labels are commonly collapsed into one number, even though they describe different things: - mg and mcg describe mass. - mL describes liquid volume. - U-100 or U-40 units describe a syringe scale tied to volume. - mg/mL or mcg/mL describes concentration. The fixed mass conversion is: `1 mg = 1,000 mcg` The syringe conversion is conditional on the scale: `U-100: 1 unit = 0.01 mL` `U-40: 1 unit = 0.025 mL` The peptide conversion is conditional on concentration: `peptide mass = concentration × volume` For example, 250 mcg is 0.25 mg. If the concentration is 2.5 mg/mL, the corresponding volume is 0.10 mL. On a U-100 syringe, 0.10 mL is 10 units. Each line uses a different relationship. No line permits “10 units” to be read as 10 mcg. Dimensional analysis catches several errors. If the desired amount is in mcg and the concentration is in mg/mL, convert one of them before dividing. If the desired amount is 250 mcg and the concentration is 2.5 mg/mL, write 250 mcg as 0.25 mg or write 2.5 mg/mL as 2,500 mcg/mL. Mixing 250 with 2.5 without conversion introduces a factor-of-1,000 error. ## How peptide amount and volume math works The phrase “peptide dosing math” usually compresses three separate calculations into one. First find concentration. Then convert the clinically specified amount into a volume. Finally convert that volume into the markings on the actual syringe. The general working is: `volume in mL = specified peptide amount ÷ concentration` For a U-100 syringe: `syringe units = volume in mL × 100` An illustrative calculation using 5 mg in 2 mL and a specified amount of 250 mcg looks like this: `5 mg ÷ 2 mL = 2.5 mg/mL` `250 mcg = 0.25 mg` `0.25 mg ÷ 2.5 mg/mL = 0.10 mL` `0.10 mL × 100 units/mL = 10 units` Every line states its unit. That is slower than copying “10 units” from a screenshot and faster than investigating an avoidable error later. The word “dose” belongs to the clinical decision, not to the syringe marking. The arithmetic can convert a prescribed amount into a volume, but it cannot select the amount, establish that a compound is appropriate, or confirm that the vial contains what its label claims. Those decisions belong to a licensed prescriber, and the material’s regulatory status still matters after the math is correct. ### Reverse-checking a calculation A forward calculation starts with a mass amount and ends with syringe units. A reverse check starts with the syringe units and asks what mass those units represent under the recorded assumptions. For a U-100 syringe, 10 units is 0.10 mL. At 2.5 mg/mL: `2.5 mg/mL × 0.10 mL = 0.25 mg` Convert back: `0.25 mg × 1,000 mcg/mg = 250 mcg` If the reverse calculation does not return the original amount, inspect the mass conversion, concentration, syringe scale, and decimal placement. This check is particularly useful after copying values into a calculator or transferring a record from one app to another. ### Comparing different diluent volumes The vial’s total stated mass remains the same in the examples below, but the amount represented by 10 U on a U-100 syringe changes: | Peptide amount in vial | Liquid volume | Concentration | 10 U on U-100 | Peptide amount in 10 U | | --- | --- | --- | --- | --- | | 5 mg | 1 mL | 5 mg/mL | 0.10 mL | 0.5 mg | | 5 mg | 2 mL | 2.5 mg/mL | 0.10 mL | 0.25 mg | | 5 mg | 2.5 mL | 2 mg/mL | 0.10 mL | 0.2 mg | This table demonstrates a relationship; it is not a schedule or recommendation. The syringe volume is constant because the scale is constant. The peptide amount changes because the concentration changes. ### Rounding and tiny volumes Rounding should happen only after the exact relationship has been written. Rounding the concentration before calculating the volume can produce a different result, particularly when the volume is small. Keep the unrounded value in the worksheet, then compare the calculated volume with the actual graduations on the syringe. A result that falls below the readable graduation is not made reliable by displaying more decimal places. The limitation is the measuring device, not the calculator. If the calculated volume does not correspond clearly to the available scale, the calculation requires review by a pharmacist or prescriber rather than an improvised adjustment. ## Three error classes behind serious mistakes The same failures recur because shorthand hides assumptions. Shorthand is useful only when the underlying inputs remain unchanged and visible. ### Error class one: reading units as an amount “Inject 12 units” is incomplete unless the syringe scale and concentration are known. On a U-100 syringe, 12 units means 0.12 mL. The peptide amount could be 0.12 mg at 1 mg/mL, 0.3 mg at 2.5 mg/mL, or 0.6 mg at 5 mg/mL. The unit is a volume marker. It becomes a mass amount only after multiplication by concentration. Treating units as mcg or mg skips the most important line in the calculation. A practical log therefore records both forms: the measured syringe volume and the calculated peptide amount, along with the concentration used. A unit entry without its vial context is not a durable record. ### Error class two: charts published without concentration A chart can look precise while omitting the variable that controls the answer. “5, 10, 15, and 20 units” may be internally consistent for one mixture and entirely different for another. Charts also travel. A screenshot survives a vial change, a new syringe, or a different diluent volume. Its visual authority does not survive those changes. If a chart does not name vial strength, diluent volume, concentration, syringe scale, and the mass amount represented, it is not a reproducible calculation. The [Bacteriostatic water calculator](https://dosyne.com/tools/bacteriostatic-water-calculator/) can help check volume and concentration relationships, but its name does not establish that bacteriostatic water is compatible with a particular compound. Compatibility and handling instructions require a verified source, not arithmetic alone. ### Error class three: logs that become uninterpretable after a vial change A log that says “20 units” has a short memory. It may be interpretable today and meaningless after the vial strength changes from 5 mg to 10 mg, the diluent volume changes from 2 mL to 1 mL, or the syringe changes from U-100 to another scale. The fix is more metadata. Record the compound name as labeled, vial strength, diluent and volume, calculated concentration, syringe type, preparation date, and the source of the clinical instruction. Mark the point where a new vial begins. Do not overwrite the old concentration. A historical entry should remain calculable from its original inputs. This matters for ordinary recordkeeping and for recognizing when two apparently identical unit entries represented different quantities. ### Error class four: decimal and unit transcription errors A decimal moved one place changes a volume by a factor of 10. A conversion from mg to mcg changes the numerical value by a factor of 1,000. These errors can enter when a label uses mg, a chart uses mcg, and a syringe uses units on the same page. Write the unit beside the number before entering it into a calculator. After the calculation, read the result aloud as a complete quantity: for example, “0.10 mL on a U-100 scale,” not merely “10.” Compare the result with the original concentration using the reverse calculation. A second person, pharmacist, or prescriber can check the worksheet when the inputs or labels are unclear. ## Reconstitution arithmetic versus physical handling Arithmetic describes the relationship between labeled mass, liquid volume, concentration, and syringe scale. It does not describe a validated aseptic process. Physical handling introduces separate variables: container closure, needle and syringe sterility, contact with surfaces, agitation, temperature, light, and repeated access to the vial. A clear solution is not proof of identity, concentration, sterility, or stability. Particles, cloudiness, discoloration, damaged closures, or an unexpected change in appearance are reasons to stop and seek qualified product-specific guidance; appearance alone cannot certify an acceptable preparation. Do not treat the amount of liquid that can be pushed into a vial as evidence that the resulting preparation is compatible or stable. Diluent choice, pH, preservatives, ionic strength, and the compound’s formulation can affect the material. A calculator has no way to evaluate those factors. ## Storage records and stability claims Storage is not a single refrigerator number. A stability claim needs a defined compound, formulation, concentration, container, temperature range, light condition, handling pattern, and testing method. Removing any of those conditions weakens the meaning of the claim. A useful preparation record can include: - compound name exactly as labeled; - stated vial strength and mass unit; - diluent name and volume; - calculated concentration and mass unit; - syringe scale used for any volume conversion; - preparation date and time, if supplied by the responsible professional; - storage condition specified by the verified instructions; - any visible change or container problem; and - the date on which the preparation was discarded, if a validated instruction specifies one. Do not infer stability from a different peptide, a different diluent, or a different vial size. A claim for a regulated pharmacy preparation does not automatically apply to material sold as research use only. Repeated punctures can also change contamination risk even if the concentration and temperature remain unchanged. Temperature labels deserve careful reading. “Refrigerated” is not identical to a particular household refrigerator setting, and a brief excursion is not automatically equivalent to continuous storage at the labeled condition. Product-specific instructions should identify what to do after an excursion. If they do not, a pharmacist or prescriber is the appropriate source of clarification. ## What this section refuses to publish This guide does not publish peptide protocols, recommended amounts, titration instructions, cycle lengths, or vendor lists. It does not convert a calculator output into an instruction to use a compound. A schedule involving semaglutide, tirzepatide, BPC-157, retatrutide, or another peptide still requires a distinction between arithmetic and clinical judgment; naming a compound does not remove that distinction. Most research peptides are not approved by the FDA or EMA for human use. Material sold as “research use only” is not manufactured to pharmaceutical standards, and purity, sterility, identity, and actual content are not guaranteed. Human evidence is thin or absent for a substantial share of research peptides, and a plausible mechanism is not evidence of safe or effective treatment. Some prescription products containing peptide medicines are regulated and have approved labeling. That status belongs to the specific product, formulation, route, indication, and manufacturing process. It does not transfer to an unrelated vial that uses the same generic compound name or to a powder sold for laboratory research. Storage is part of the calculation record, but a calculator cannot manufacture stability data. Temperature, light, agitation, container closure, preservatives, contamination during handling, and time after reconstitution all matter. Use current instructions from a qualified pharmacy or prescriber when they exist; do not invent a universal refrigerator timeline from an internet chart. This boundary is deliberate. A protocol tells someone what to do with a particular substance. A reference calculation shows how numbers relate and exposes the assumptions. The latter is useful without pretending to settle the former. ## A practical map through the subject If you are documenting a vial for the first time, start with a worksheet that names every input: vial strength, diluent volume, concentration, syringe type, and preparation date. Keep the original label and write the calculation before transferring anything. The [Five free calculators, and the arithmetic behind them](https://dosyne.com/tools/) provides the broader set of unit and volume checks, while the reconstitution calculator handles the central equation. If you are checking somebody else’s chart, work backward. Ask what syringe scale it assumes, what volume is represented by the stated units, what concentration was used, and which vial strength produced that concentration. If any answer is missing, label the chart incomplete rather than guessing its hidden values. If you are trying to understand a schedule you were given, separate the schedule from the conversion. Identify the clinically specified amount and frequency as instructions from the responsible clinician, then use the recorded concentration and syringe type to understand the corresponding volume. Do not substitute a copied chart for clarification from the prescriber or pharmacist. If your main problem is remembering which vial was active on a particular date, start with the log rather than the calculator. A calculator can reproduce a number; only a dated vial record can show which number applied. For readers comparing tracking approaches, [How the peptide trackers actually differ](https://dosyne.com/compare/) is a better starting point than a feature list detached from recordkeeping. A private device can help with bookkeeping. Dosyne performs its calculations on the phone, with no account, server, or data leaving the device, and it can keep vial and dose context together. Search for “Dosyne Peptide Calc & Tracker” in the App Store or Google Play. The privacy model does not validate a peptide or make a clinical decision; it keeps sensitive arithmetic and records on the device. ## A one-page worksheet Before accepting a result, write the following in a single block rather than scattering the values across messages or screenshots: `Vial strength: ____ mg` `Diluent volume: ____ mL` `Concentration: ____ mg/mL` `Syringe scale: U-100, U-40, or mL graduations: ____` `Measured volume: ____ mL` `Equivalent syringe marking: ____ units, if applicable` `Calculated peptide amount: ____ mg or ____ mcg` The concentration line should be reproducible from the first two lines. The calculated amount should be reproducible from concentration and measured volume. If either relationship fails, stop at the worksheet and resolve the discrepancy before relying on the result. A complete worksheet also makes changes visible. If the vial strength, diluent volume, syringe type, or labeled preparation changes, begin a new entry. Do not edit the old concentration to match the new vial. Historical arithmetic is useful only when its original assumptions remain intact. ## Bottom line Reject any syringe number that lacks its vial strength, diluent volume, concentration, and syringe scale. Calculate concentration first, keep mg and mcg conversions explicit, translate volume into the actual syringe marking only after that, and preserve each preparation in a dated log. The arithmetic can verify a relationship between labeled inputs; it cannot verify identity, purity, sterility, stability, regulatory approval, or a clinically appropriate amount. ## Every article in this section [Jul 30, 2026 **Peptide tracker app: what it actually needs to do** Peptide tracker app comparison: which apps keep the concentration attached to every logged dose, survive a vial change, and export a history a clinician can read.](https://dosyne.com/lab/peptide-tracker-apps/)[Jul 28, 2026 **Peptide reconstitution mistakes: nine ways to quietly ruin a vial** Peptide reconstitution mistakes can ruin a vial or distort a dose. Learn the failure modes, concentration math, syringe errors, and discard signals.](https://dosyne.com/lab/reconstitution-mistakes/)[Jul 26, 2026 **Subcutaneous injection site rotation that holds up** Subcutaneous injection site rotation protects usable tissue and reduces absorption variability. Learn how to map zones, spot lipohypertrophy, and log sites.](https://dosyne.com/lab/injection-site-rotation/)[Jul 24, 2026 **Peptide cycle length: where the numbers come from** Peptide cycle length explained: trace eight- and twelve-week conventions, check concentration and syringe arithmetic, and keep dated records instead of guessing.](https://dosyne.com/lab/peptide-cycle-length/)[Jul 23, 2026 **Peptide dosage charts: the math they omit** Peptide dosage charts can hide concentration, syringe-scale, and unit-conversion errors. Learn how to audit vial math without turning arithmetic into dosing advice.](https://dosyne.com/lab/peptide-dosage-charts/)[Jul 22, 2026 **BPC-157 dosage calculator: what charts omit** BPC-157 dosage calculator explained through concentration math, 5 mg and 10 mg examples, syringe-unit conversions, storage limits, and evidence gaps.](https://dosyne.com/lab/bpc-157-dosing-arithmetic/)[Jul 21, 2026 **GLP-1 titration schedule: How Escalation Works** GLP-1 titration schedule explained: see how exposure, gastrointestinal tolerance, concentration, syringe units, and storage records affect interpretation.](https://dosyne.com/lab/glp1-titration-schedules/)[Jul 20, 2026 **Tirzepatide dosage chart in units: why charts disagree** Tirzepatide dosage charts in units are concentration-specific. Learn the mg-to-mL-to-unit math, U-100 conversions, reconstitution checks, rounding, and chart.](https://dosyne.com/lab/tirzepatide-units-explained/)[Jul 19, 2026 **Semaglutide units chart: why the same dose is a different number of units** A semaglutide units chart explaining mg per U-100 syringe unit at each concentration, with formulas for converting milligrams, milliliters, and units.](https://dosyne.com/lab/semaglutide-units-explained/)[Jul 18, 2026 **How to store peptides after reconstitution: stability rules** Learn how refrigeration, light, air, handling, diluent choice and freezing affect reconstituted peptide stability, with practical storage and arithmetic guidance.](https://dosyne.com/lab/peptide-storage-after-reconstitution/)[Jul 17, 2026 **Mcg to units on an insulin syringe** Convert mcg to units on a U-100 insulin syringe with concentration formulas, worked examples, syringe-scale checks, and a practical error checklist.](https://dosyne.com/lab/mcg-to-units-on-an-insulin-syringe/)[Jul 16, 2026 **How to read an insulin syringe for peptides** Learn how to read a U-100 insulin syringe, convert peptide concentration into milliliters and units, and catch mg-to-mcg and scale errors.](https://dosyne.com/lab/read-an-insulin-syringe/)[Jul 15, 2026 **How much bacteriostatic water to add to peptide vials** Learn the concentration and U-100 syringe math for peptide reconstitution, compare diluent volumes, and separate sterility from storage stability.](https://dosyne.com/lab/bacteriostatic-water-for-peptides/)[Jul 14, 2026 **How to Reconstitute Peptides: The Arithmetic** Learn how peptide reconstitution math works, from vial strength and concentration to syringe units, dilution checks, handling, storage, and rounding.](https://dosyne.com/lab/how-to-reconstitute-peptides/) ## Frequently asked questions How do you calculate peptide reconstitution? Divide the vial’s total peptide amount by the volume of diluent added. For example, 5 mg in 2 mL produces 2.5 mg/mL. Convert units only after finding that concentration. With a U-100 syringe, 1 mL equals 100 units, so 0.1 mL equals 10 units. The arithmetic describes volume; it does not determine a medically appropriate amount. How much bacteriostatic water should be added to a peptide vial? There is no universal volume. The amount changes the resulting concentration and the volume drawn for any prescribed amount. Use the product’s verified instructions and the prescriber’s or pharmacist’s direction. Bacteriostatic water is not interchangeable with every diluent, and a calculation cannot confirm sterility, compatibility, or storage stability. What does 10 units mean on an insulin syringe? On a standard U-100 insulin syringe, 10 units means 0.10 mL because 100 units equal 1 mL. It does not mean 10 micrograms or 10 milligrams. The peptide amount depends on concentration: at 2.5 mg/mL, 0.10 mL contains 0.25 mg, or 250 micrograms. U-40 and other syringe scales produce different conversions. How long is reconstituted peptide stable? No single stability period applies to all reconstituted peptides. Stability depends on the compound, diluent, concentration, container, temperature, light exposure, handling, and validated sterility data. A label may provide a beyond-use instruction, but research-use material may have no reliable human-use stability standard. Do not infer shelf life from appearance alone. Can you use bacteriostatic water for every peptide? No. Compatibility depends on the compound and formulation. Bacteriostatic water contains a preservative and is not a universal solution for every vial or route of administration. It also cannot make questionable material sterile or pharmaceutical grade. Follow verified product and pharmacy instructions rather than copying a diluent choice from an unrelated chart. Why do peptide dosing charts give different syringe-unit numbers? The charts may assume different vial strengths, diluent volumes, concentrations, syringe types, or target amounts. A chart that says “10 units” without identifying those inputs is incomplete. The same 10 units on a U-100 syringe always represents 0.10 mL, but that volume contains different peptide amounts at different concentrations. Are research peptides approved for human use? Most research peptides are not approved by the FDA or EMA for human use. Material sold as “research use only” is not manufactured to pharmaceutical standards, and its purity, sterility, identity, and actual content are not guaranteed. Some prescription medicines are regulated products, but their approved labeling does not transfer to unrelated research material. What is the safest way to check a peptide calculator result? Recalculate from four recorded inputs: vial strength, diluent volume, resulting concentration, and syringe type. Then check the units at every step: mg, mcg, mL, and syringe units. If a chart omits an input, do not treat its result as verifiable. A calculator checks arithmetic; it cannot validate the material, sterility, prescription, or clinical decision. ### The same arithmetic, in your pocket Dosyne keeps the concentration attached to every logged dose, so a history stays readable months later. Free on iPhone and Android, no account. [Get the app](https://dosyne.com/get/) Free · no account · nothing leaves your phone --- HTML version: https://dosyne.com/lab/ Structured data for this site: https://dosyne.com/api/v1/openapi.json · https://dosyne.com/llms.txt Dosyne publishes arithmetic, not protocols: nothing here is a dose recommendation, and dosing decisions belong to a licensed prescriber. Free to quote and reuse with a link back to the source URL above (CC BY 4.0). --- **Best Peptide Tracker App: How Trackers Differ | Dosyne** > Best peptide tracker app comparison: test concentration math, vial changes, syringe units, site logs, exports, privacy, and spreadsheet alternatives before you. Source: https://dosyne.com/compare/ [Home](https://dosyne.com/)/Compare Compare # Best peptide tracker app: how peptide trackers differ Best peptide tracker app comparison: test concentration math, vial changes, syringe units, site logs, exports, privacy, and spreadsheet alternatives before you. | App | Developer | Rating | Ratings | Updated | | --- | --- | --- | --- | --- | | Peptide Calc & Tracker: DosyneThis app | Vast Flow, LLP | New | No ratings yet | 30 Jun 2026 | | [Shotsy GLP-1 Tracker](https://dosyne.com/compare/dosyne-vs-shotsy-glp-1-tracker/) | Shotsy Co. | 4.84 | 28,325 | 16 Jul 2026 | | [MeAgain: GLP-1 Tracker App](https://dosyne.com/compare/dosyne-vs-meagain-glp-1-tracker-app/) | DOTS FUTURE TECHNOLOGIES INC | 4.80 | 26,296 | 20 May 2026 | | [PeptidePal – Peptide Tracker](https://dosyne.com/compare/dosyne-vs-peptidepal-peptide-tracker/) | Blank Labs LLC | 4.69 | 3,262 | 16 Jul 2026 | | [Pep AI: Peptide GLP-1 Tracker](https://dosyne.com/compare/dosyne-vs-pep-ai-peptide-glp-1-tracker/) | Zode Development LLC | 4.72 | 2,566 | 24 Jul 2026 | | [Peptide Tracker Log & Reminder](https://dosyne.com/compare/dosyne-vs-peptide-tracker-log-and-reminder/) | Flat Six Labs LLC | 4.93 | 1,175 | 29 Jul 2026 | | [PepCalc: Peptide Calculator](https://dosyne.com/compare/dosyne-vs-pepcalc-peptide-calculator/) | Awesome Labs LLC | 4.80 | 947 | 25 Jun 2026 | App Store data for the United States storefront, read on 31 July 2026. A rating count measures install base and age rather than quality — ours is a new app and the table says so rather than leaving the row out. An app can show 20 syringe units for one calculation and 10 for another even when the recorded amount is 1 mg. The difference is concentration, and it is the first test of any peptide tracker. That question is the center of this peptide tracker comparison. The category includes dedicated peptide logs, medication reminders, general health apps, spreadsheets, and paper records. They differ less in their screenshots than in what they preserve after a new vial, a different reconstitution volume, a missed entry, a new injection site, an edited record, or a subscription that ends. A tracker is a recordkeeping tool, not a laboratory test and not a prescribing tool. Its arithmetic can describe the volume represented by stated inputs. It cannot establish that a vial contains the labeled compound, that the material is sterile, or that a research peptide is appropriate for human use. The sourcing rules here are plain. Figures come from Apple’s public App Store listing data, checked on March 15, 2026. Feature descriptions come from each developer’s own store listing. We do not infer a feature from a screenshot, assume that a vague claim means a specific workflow, or speculate about what cannot be verified. Store listings change, so check the current listing before treating a price, rating count, update date, or feature statement as permanent. A rating count is not a quality score. It mostly reflects install base and age, with a contribution from how strongly users feel about the product. A newer app can have solid engineering and very few ratings; an older app can have thousands of ratings while its data model remains primitive. A recent update date is a better maintenance signal than either rating count or star average. It does not prove calculation quality, but it shows that someone still owns the software and its dependencies. ## The test that separates useful trackers from decorative ones ### 1. Concentration must live beside every dose This is the decisive criterion. A logged amount such as 1 mg is not enough information to reconstruct syringe volume. The same amount can occupy different volumes when concentration changes, and concentration changes when vial strength or final liquid volume changes. Suppose a vial contains 10 mg and the working volume is 2 mL. Its concentration is: ``` 10 mg ÷ 2 mL = 5 mg/mL ``` An amount of 1 mg then corresponds to: ``` 1 mg ÷ 5 mg/mL = 0.2 mL ``` On a U-100 insulin syringe, where 100 units represent 1 mL: ``` 0.2 mL × 100 units/mL = 20 units ``` Now take the same 10 mg vial with a 1 mL working volume: ``` 10 mg ÷ 1 mL = 10 mg/mL 1 mg ÷ 10 mg/mL = 0.1 mL 0.1 mL × 100 units/mL = 10 units ``` The amount stayed at 1 mg. The syringe reading changed from 20 units to 10 units. A history that stores only “1 mg” loses the information needed to interpret the liquid volume. A tracker that treats concentration as a current setting rather than a property of each entry can silently make old records misleading when the current vial changes. A sound data model stores the vial strength, working volume, resulting concentration, recorded amount, calculated volume, syringe scale, and syringe-unit result together. It should also preserve the original values if the entry is later edited. Dosyne’s central calculation follows that chain on the device rather than requiring the user to perform each conversion separately. The [Peptide reconstitution calculator](https://dosyne.com/tools/peptide-reconstitution-calculator/) shows the same arithmetic without requiring a tracker. The input labels matter. “Amount,” “volume,” “concentration,” and “units” are not interchangeable. A good interface makes the direction of the conversion clear and does not use “units” as a synonym for milligrams. It should also display the unit beside every value in the result, not rely on a heading several screens away. ### 2. It must survive a mid-cycle vial change A tracker should not force one compound into one permanent concentration. A new vial may have a different strength, or the working volume may differ from the previous vial. Neither event changes the historical facts about earlier entries. The correct data model looks more like this: | Record | Vial strength | Working volume | Concentration | Amount recorded | Volume at that concentration | U-100 equivalent | | --- | --- | --- | --- | --- | --- | --- | | Entry A | 10 mg | 2 mL | 5 mg/mL | 1 mg | 0.20 mL | 20 units | | Entry B | 10 mg | 1 mL | 10 mg/mL | 1 mg | 0.10 mL | 10 units | The table is not a dosing recommendation. It demonstrates why a vial event belongs in the record. An app that silently applies today’s concentration to yesterday’s entries is not preserving a history; it is rewriting one. Look for an explicit “new vial” action, separate vial records, or an equivalent mechanism. A free-text note saying “new vial” is better than nothing, but it leaves the arithmetic dependent on memory. It also makes a later export harder for a clinician to interpret. The app should distinguish at least three events: 1. A vial is created or opened. 2. A working concentration is entered or calculated. 3. An amount is logged against that vial. Those events do not have to appear as three separate screens, but the underlying record should preserve the relationship. If the application permits a user to change a concentration globally, check whether it warns that historical entries will change. A global edit can be convenient for correcting a typo, but dangerous if it is actually a new-vial event. ### 3. Injection-site records are practical, not ornamental A body map is useful only if it records the site associated with a particular dated entry and lets the user review the sequence later. A generic note field can perform the same job if it is easy to use consistently. A decorative illustration that does not attach a site to a specific entry is not a site log. The value is historical: a user can see where an injection occurred and whether the record contains repeated entries in one area. That does not establish that any particular site is appropriate for a compound. Site selection and injection technique are clinical matters, not app settings. Check the granularity of the map. “Abdomen” is a different record from “left abdomen,” and “thigh” may be different from a more specific location. The best level depends on what the user needs to remember, but the app should not imply a precision that the interface cannot consistently reproduce. A site field should also be optional when the user cannot confidently reconstruct an old entry; forcing a guess produces false precision. A useful site history includes the date, the selected location, and any note attached to the entry. It should not turn a map into an instruction about where to inject or how to rotate sites. ### 4. Export should be readable by a clinician An export is not useful merely because it produces a CSV file. A clinician needs dates, compound names, amounts, units, concentration, vial context, injection site, and notes in a form that does not require reverse engineering the app’s private database schema. Test an export before trusting it. Open the file outside the app and check the following: - Do dates retain the time and time zone, or are they reduced to a day? - Does every numeric field carry a unit? - Does concentration travel with each entry? - Does a vial change appear as a real event rather than disappear into a note? - Are edited entries marked, or is the original value overwritten? - Are blank fields distinguishable from zero values? - Can the file be opened in ordinary spreadsheet software? - Does the export include all history or only the currently displayed range? A PDF can be easy to read but difficult to analyze. A CSV can be easy to analyze but unattractive to read. Offering both is better, although a clean CSV with explicit column names is more valuable than a visually polished report that omits concentration. Privacy belongs in the same test. Determine whether the export is manual, whether records synchronize to a server, whether analytics are connected to health entries, and whether deletion actually removes local data. A privacy policy should identify the categories of information collected and the purpose of collection; a vague promise that data is “secure” does not answer those questions. Dosyne does not require an account and performs its calculations on the phone; its stated design keeps the dose log on the device rather than sending it to a server. A local-only design also creates a backup trade-off. If the record never leaves the device, losing the phone or deleting the app may remove the only copy. Before choosing a local tracker, confirm whether the operating system backup includes its data and whether a manual export is available. Privacy and recoverability are separate properties. ### 5. Missed-dose handling should record an event, not invent a correction A missed entry and a missed dose are different facts. A good tracker lets the user mark what happened, add a note, and preserve the original schedule without automatically shifting future entries or generating a catch-up instruction. The app should also distinguish “not logged yet” from “did not occur.” Those states look identical on a simple calendar. A status such as scheduled, completed, skipped, missed, or unknown creates a more honest history than filling every blank with an assumption. That restraint matters. A calendar can show that an event did not occur; it cannot determine what should happen next. If a person misses a prescribed medication dose, the next action belongs to the prescribing clinician or the medication’s official instructions. A tracker should record the decision, not make one. Notifications need the same boundary. A reminder can say that a scheduled record is due, but it should not present an unsupervised change, catch-up amount, or altered interval as an instruction. The difference is not cosmetic: a reminder reports a calendar state, while a dosing recommendation directs a health decision. ### 6. Subscription failure should not destroy the record Before paying, ask what happens when a trial or subscription ends. Can existing entries still be viewed? Can they be exported? Do reminders stop while history remains available? Does the app lock the record behind a renewal screen? Can a user cancel without deleting the record? The answer is part of the product, not an administrative detail. A dose log is longitudinal by nature. If historical data becomes inaccessible at the moment payment stops, the app has created lock-in around a health record. A subscription can fund maintenance; it should not make the past unreadable. Also check whether a paid feature is required to export. An app that lets a user enter years of records but restricts the only backup route to a premium tier deserves closer scrutiny. The same applies to account deletion: a user should know whether deletion removes cloud records, local records, or both, and whether an export is available first. ### 7. Corrections should be visible Health records need corrections, but silent corrections weaken them. If a user changes an amount, vial, concentration, date, or site, the app should make the change understandable. That can mean an edit history, a correction note, or a visible “last modified” field. A tracker does not need a complex audit system to be useful. It does need to avoid a design in which the current value replaces the old value with no indication that anything changed. A neat timeline is less valuable than an honest one. This is especially relevant to concentration. Correcting a typographical error in a vial strength is not the same event as starting a new vial. The interface should make those actions distinct, because one changes the interpretation of an existing entry and the other should not. ## The arithmetic a tracker must get right The calculation has three stages. First, find concentration. Second, find the liquid volume represented by the stated amount. Third, convert that volume to the syringe scale. ``` concentration = vial strength ÷ final liquid volume volume represented = stated amount ÷ concentration syringe units = volume represented × syringe units per mL ``` Keep units consistent. If strength is in milligrams and volume is in milliliters, concentration is mg/mL. If the stated amount is in micrograms, convert it before dividing: ``` 1 mg = 1,000 mcg ``` For example, a 5 mg vial with a 2 mL working volume gives: ``` 5 mg ÷ 2 mL = 2.5 mg/mL ``` An amount of 250 mcg is 0.25 mg: ``` 0.25 mg ÷ 2.5 mg/mL = 0.1 mL 0.1 mL × 100 units/mL = 10 U-100 units ``` The result is arithmetic based on the stated inputs. It is not evidence that the material contains 5 mg, that the working volume is accurate, or that the calculated amount is medically appropriate. ### Why the order of operations matters A tracker should not jump directly from milligrams to syringe units without showing concentration. The intermediate value is what makes the result auditable: ``` amount → liquid volume → syringe scale ``` If an app displays only “10 units,” a user cannot tell whether it used 2.5 mg/mL, 5 mg/mL, a different syringe scale, or a rounding rule. Showing the intermediate concentration and volume makes a wrong input easier to find. Rounding also belongs in the interface. The mathematically calculated volume may contain more decimal places than the syringe can display. The app should show the unrounded result, the displayed rounded result, and the selected syringe increment where practical. It should not imply that a physical graduation can measure a value more precisely than the device allows. For instance, if a result is 0.137 mL, the corresponding U-100 value is 13.7 units. A syringe with whole-unit graduations cannot represent that value in the same way as a device with finer markings. The application can report the arithmetic, but it should not turn rounding into an unspoken dosing instruction. ### “Units” is a scale, not a universal amount “Units” is not a universal volume. On a U-100 syringe, 100 units equal 1 mL, so one unit equals 0.01 mL. Other syringe scales do not share that relationship. The syringe label must match the conversion used by the calculator. A tracker should ask for the syringe scale or clearly state the scale assumed. It should not label every syringe as U-100, and it should not accept a unit value without identifying whether that value means syringe markings, biological activity units, or another measure. The word “unit” has meaning only in context. The [Insulin syringe unit visualizer](https://dosyne.com/tools/insulin-syringe-visualizer/) is useful for checking how a calculated volume maps to graduations, while the [mcg to units converter](https://dosyne.com/tools/mcg-to-units-converter/) handles the unit conversion explicitly. ### Micrograms and milligrams need explicit conversion A factor of 1,000 separates milligrams and micrograms. A tracker should display that conversion rather than rely on the user to remember it: ``` 1 mg = 1,000 mcg 0.5 mg = 500 mcg 0.25 mg = 250 mcg ``` A field that accepts “250” without identifying whether the value is milligrams or micrograms is unsafe as a data model. The same numeric input has radically different meaning under the two units. The unit should be stored with the value, included in exports, and visible in the result. ### Final volume is an assumption worth displaying The final liquid volume deserves attention. If a powder occupies volume after dissolving, the actual final volume may not equal the amount of diluent added. In informal calculations, people may use the diluent volume as the working volume. That assumption can be materially wrong, especially at small volumes. A calculator should make the input assumption visible rather than disguise it as laboratory precision. “Diluent added” and “final volume” are not automatically identical fields. If the user does not know which value is appropriate, the app cannot resolve that uncertainty through arithmetic. The [Bacteriostatic water calculator](https://dosyne.com/tools/bacteriostatic-water-calculator/) can handle volume arithmetic, but it cannot certify sterility or extend a preparation’s beyond-use date. ### Storage stability is not a calculator output The arithmetic does not determine stability. Storage temperature, light exposure, container closure, solvent, concentration, preparation method, and the compound’s chemistry all matter. There is no universal “reconstituted peptide lasts X days” rule. An app should provide a preparation date, an opened-vial date, a storage note, and perhaps a field for a date supplied by a pharmacist or prescriber. It should not manufacture a stability guarantee from the compound name alone. A countdown label can look authoritative even when the underlying information is incomplete. The same limitation applies to freezing, refrigeration, transport, and temperature excursions. A tracker can record that an event happened. It cannot determine from a generic storage label whether a particular preparation remains suitable. ## Data fields that deserve separate treatment A useful tracker is not simply a calendar with a compound name. Its fields determine whether the history can be interpreted later. ### Compound name The name should be entered as text that can be distinguished from a brand, formulation, or research label. If the app supplies a fixed list, it should allow a custom entry without implying that listing a compound establishes approval or safety. The same compound can appear in more than one concentration, vial strength, or formulation. Therefore, the compound name should not be the key that controls every later calculation. Vial and concentration context belong to the entry. ### Date and time A date-only record may be enough for a simple history, but time matters when entries occur close together or when a user reviews a missed event. The app should clarify whether it uses the phone’s local time, UTC, or the time zone associated with the original entry. Time-zone handling becomes visible during travel or after restoring a backup. A record that moves from one date to another because the app converted it silently is difficult to audit. Export should preserve the original time zone or state that it does not. ### Amount and volume Some users think in mass, some in liquid volume, and some in syringe markings. A well-designed tracker can store all three while identifying which value was entered and which values were calculated. It should not overwrite a calculated value when the user changes a display preference. The app should also prevent impossible unit combinations from passing silently. A concentration in mg/mL cannot be divided into an amount labeled in mcg without conversion. Input validation is part of the calculation, not a decorative feature. ### Vial identity A vial identifier does not need to be a serial number. It can be a user-created label such as Vial A or an opening date. Its purpose is to keep entries from separate preparation events distinct. A useful vial record can include strength, working volume, concentration, preparation date, storage note, and status. Status might distinguish current, finished, discarded, or unknown. These labels record what the user reports; they do not certify the material. ### Notes Notes are useful for context that does not fit a fixed field, but a notes box should not be the only place where important arithmetic inputs are stored. If concentration exists only in prose, the app cannot reliably calculate, sort, or export it. Notes can identify a correction, a storage observation, a question for the clinician, or an unusual event. They should not be used to create an automated dosing protocol. ## Peptide app versus spreadsheet The spreadsheet is a serious alternative. It wins on flexibility, ownership, transparency, and cost. A careful user can create a vial table, calculate concentration with visible formulas, preserve every historical concentration, add custom fields, and export the entire file without waiting for a developer to support a format. A robust spreadsheet might use separate tables for compounds, vials, and entries. The entry table can reference a vial identifier rather than copying a current concentration into every row. That structure reduces the chance that changing the current vial will alter old calculations. It also makes it easier to filter entries by vial, date, site, or unit. The spreadsheet exposes its own failure modes. A copied formula can point to the wrong row. A cell formatted as a date can corrupt a value. A user can overwrite a concentration, sort one column without the others, or make a hidden assumption about U-100 units. Backups and version history matter. So does testing the sheet with two vials that have different concentrations. A simple test dataset should include at least these cases: - Two vials with the same strength but different working volumes. - Two entries with the same amount but different concentrations. - One entry recorded in micrograms and another in milligrams. - A syringe scale other than U-100. - A corrected entry whose original value remains identifiable. - A blank field that must not be interpreted as zero. An app earns its place by reducing those repeated tasks. It can keep vial state, calculate volume and units, prompt for a site, show a reminder, and prevent a historical record from changing when the current vial changes. It can also conceal its assumptions, which is why visible working and export matter more than a pleasant interface. The sensible peptide app versus spreadsheet decision is therefore personal. Choose the spreadsheet if you want to inspect and control every formula and will maintain it. Choose an app if the friction of entering formulas, managing reminders, and preserving vial context is the reason your records become incomplete. Neither option verifies the material being logged. A hybrid approach can work: use an app for day-to-day entry, export at a defined interval, and retain an independent copy. That arrangement creates another responsibility: compare the export with the in-app history and confirm that concentration, units, dates, and vial identifiers survived the transfer. Dosyne is one of the smaller apps in this comparison. That is a fact about scale, not an argument against the alternatives. Its narrower design emphasizes on-device arithmetic, dose and vial history, injection-site mapping, reminders, and no account. Search for “Dosyne Peptide Calc & Tracker” in the App Store or Google Play. ## What a comparison can and cannot establish A store listing can establish what a developer says the app does. It cannot establish calculation accuracy across every edge case, the quality of customer support, the resilience of a database after years of use, or the medical appropriateness of a workflow. Those require testing, documentation, and sometimes direct questions to the developer. The same limit applies to ratings. Reviews can reveal recurring complaints about bugs, billing, or missing features, but they are not controlled evaluations. A high rating does not prove that concentration is stored per entry. A low rating does not prove that an app’s arithmetic is wrong. The comparison also does not rank compounds. Semaglutide, tirzepatide, BPC-157, retatrutide, and other names may appear in logs, but a tracker does not supply evidence of efficacy. Most research peptides are not approved by the FDA or EMA for human use. Products sold as “research use only” are not manufactured to pharmaceutical standards, and purity, sterility, and actual content are not guaranteed. That distinction is easy to lose because software makes a record look official. A precise calculation can tell you the volume represented by stated inputs. It cannot tell you whether the vial contains what its label claims, whether it is sterile, or whether the compound has an established human-use profile. The calculation is exact only relative to the inputs. A tracker also cannot identify counterfeit labeling, degradation, contamination, incorrect storage, or a mismatch between a product’s stated and actual concentration. Those are material and clinical questions outside the app’s data model. A clean export is evidence of what was entered, not independent confirmation of what was in a container. ## A practical audit before choosing an app Run the same checks on every candidate. Create two vial records with different concentrations and log the same milligram amount under each. Confirm that the syringe-unit results differ correctly and that the old entry does not change when the new vial becomes current. Then test the following workflow: 1. Create a vial with a stated strength and working volume. 2. Confirm that the app displays concentration with units. 3. Record an amount and inspect the calculated liquid volume. 4. Select the syringe scale and check the conversion. 5. Create a second vial with a different concentration. 6. Record the same amount against the second vial. 7. Compare both historical entries. 8. Add an injection site and a note. 9. Mark a scheduled event as missed without accepting an automatic correction. 10. Edit one entry and check whether the change is visible. 11. Export the history and open it outside the app. 12. Simulate a subscription lapse or read the developer’s terms carefully. If the app cannot answer what happens to the record after cancellation, deletion, device loss, or a subscription lapse, treat that uncertainty as a product limitation. If it cannot show which concentration produced a syringe-unit result, do not treat a polished interface as a substitute for a transparent calculation. For independent arithmetic, [The Lab — reconstitution arithmetic, written by people with nothing to sell](https://dosyne.com/lab/) explains concentration, volumes, syringe scales, and the limits of the calculation. [Five free calculators, and the arithmetic behind them](https://dosyne.com/tools/) keeps the same work visible instead of reducing it to a result with no units. A tracker should also make corrections auditable. If an entry is edited, the user should be able to tell what changed. Quietly replacing an amount, concentration, or vial identity produces a neat timeline and a weak record. A correction note is less tidy and more honest. ## Questions worth asking the developer Before installing or subscribing, ask questions that the screenshots cannot answer: - Is concentration stored independently for each entry? - Can one compound have multiple active or historical vials? - Does changing the current vial alter previous calculations? - Which syringe scales are supported? - Does the app distinguish mg, mcg, mL, and syringe units? - Are calculated values retained after an edit? - Can the complete history be exported without a paid plan? - Is export available as both a readable report and structured data? - Is an account required, and where is health data stored? - What data is sent to analytics or third-party services? - What happens to local and cloud records after account deletion? - Can the app be used if the developer stops maintaining it? A direct answer is more useful than a feature label. “Dose calculator” does not reveal whether the calculation includes vial strength, final volume, or syringe scale. “Cloud backup” does not reveal whether the data is encrypted, exportable, or deleted when an account closes. ## Bottom line The best peptide tracker app is the one that preserves concentration with every entry, handles a vial change without rewriting history, distinguishes a missed event from an automatic correction, records site and notes, exports a human-readable record, shows its unit arithmetic, and leaves the data accessible after payment stops. A spreadsheet remains the best tool for a careful person who wants complete control, visible formulas, and independent backups. A focused app earns its place when it reliably handles arithmetic, vial history, reminders, and site records without hiding its assumptions. On the evidence available here, judge every product by its data model and export before its ratings, body map, or feature count. Those interface details matter only after the underlying history remains interpretable. ## Every comparison [28,325 ratings **Dosyne vs Shotsy GLP-1 Tracker** Choose Shotsy for broad GLP-1 tracking and analytics; choose Dosyne for local-first reconstitution arithmetic and a focused dose log.](https://dosyne.com/compare/dosyne-vs-shotsy-glp-1-tracker/)[26,296 ratings **Dosyne vs MeAgain: GLP-1 Tracker App** Choose MeAgain for broad GLP-1 habit tracking; choose Dosyne for transparent reconstitution arithmetic and a private dose log.](https://dosyne.com/compare/dosyne-vs-meagain-glp-1-tracker-app/)[3,262 ratings **Dosyne vs PeptidePal – Peptide Tracker** Choose PeptidePal for protocols, stacks, and peptide reference material; choose Dosyne for transparent arithmetic, local-only records, and a focused dose log.](https://dosyne.com/compare/dosyne-vs-peptidepal-peptide-tracker/)[2,566 ratings **Dosyne vs Pep AI: Peptide GLP-1 Tracker** Choose Pep AI for broad wellness records; choose Dosyne for local-first dose arithmetic, vial logs, site rotation, and reminders.](https://dosyne.com/compare/dosyne-vs-pep-ai-peptide-glp-1-tracker/)[1,175 ratings **Dosyne vs Peptide Tracker Log & Reminder** Choose Peptide Tracker for a broad protocol journal; choose Dosyne for local-first reconstitution arithmetic and a focused dose log.](https://dosyne.com/compare/dosyne-vs-peptide-tracker-log-and-reminder/)[947 ratings **Dosyne vs PepCalc: Peptide Calculator** Choose PepCalc for flexible laboratory calculations and blend protocols; choose Dosyne for private dose records, site mapping, and reminders.](https://dosyne.com/compare/dosyne-vs-pepcalc-peptide-calculator/) ## Frequently asked questions What is the best peptide tracker app? There is no universal best peptide tracker app. The decisive test is whether each logged amount retains the concentration used at that time, followed by vial changes, injection sites, readable export, missed-event handling, and data access after a subscription ends. A small app that preserves this context can be more useful than a popular app with a larger rating count but thinner records. How do peptide tracker apps compare with a spreadsheet? A spreadsheet can be the better choice for people who want total control, no subscription, custom fields, and easy long-term export. An app usually reduces repeated arithmetic and may handle unit conversion, vial state, injection-site mapping, and reminders more conveniently. A spreadsheet is only as reliable as its formulas and backups; an app is only as reliable as its data model and the assumptions built into it. What should a peptide tracker record? At minimum, a peptide tracker should record the date and time, compound name, amount, units, concentration, vial identity or vial change, injection site, and relevant notes. The concentration must remain attached to the individual entry. A history containing only milligram values becomes ambiguous after a reconstitution change, even if every entry was typed correctly. Are peptide tracker apps safe to use? A tracker can reduce arithmetic and recordkeeping errors, but it cannot verify a vial's identity, purity, sterility, potency, storage history, or suitability for human use. Most research peptides are not approved by the FDA or EMA for human use. Material labeled research use only is not manufactured to pharmaceutical standards, and its purity, sterility, and actual content are not guaranteed. Dosing decisions belong to a licensed prescriber. What is the best GLP-1 tracker app comparison criterion? For a GLP-1 tracker app comparison, check first whether concentration is attached to every entry and whether the app supports a mid-cycle vial change without altering earlier records. Then check missed-event notes, injection-site history, export quality, reminders, and what remains available if a subscription lapses. A titration planner can display a schedule, but software should not turn a calendar into a dosing decision; that belongs to the prescribing clinician. Can a peptide app convert milligrams to insulin syringe units? A peptide app can convert milligrams to syringe units only when it has the vial strength, final liquid volume, and syringe scale. The calculation is concentration in mg/mL, followed by the liquid volume represented by the stated amount, followed by the syringe conversion. Without concentration, a milligram-to-units result is undefined. A trustworthy app should show the working rather than present a bare number. Do peptide tracker apps work without an account? Some peptide tracker apps work without an account, and an account is not inherently necessary for dose logging. The relevant questions are where records are stored, whether they leave the device, whether backup or export exists, and what happens after deletion or a subscription lapse. Dosyne performs its calculations on the device and does not require an account or send dose-log data to a server. Is a peptide tracker worth paying for? A peptide tracker is worth paying for only if it prevents a problem you would otherwise manage poorly, such as repeated syringe arithmetic, incomplete records, forgotten vial changes, or an unusable history. A spreadsheet may be sufficient for someone who already maintains formulas and backups. Before subscribing, test the data export, concentration model, correction history, and post-lapse access. A reminder alone is not much of a product. ### The same arithmetic, in your pocket Dosyne keeps the concentration attached to every logged dose, so a history stays readable months later. Free on iPhone and Android, no account. [Get the app](https://dosyne.com/get/) Free · no account · nothing leaves your phone --- HTML version: https://dosyne.com/compare/ Structured data for this site: https://dosyne.com/api/v1/openapi.json · https://dosyne.com/llms.txt Dosyne publishes arithmetic, not protocols: nothing here is a dose recommendation, and dosing decisions belong to a licensed prescriber. Free to quote and reuse with a link back to the source URL above (CC BY 4.0). --- **Insulin Syringe and Reconstitution Reference API — JSON, No Key** > Keyless CORS-open JSON over the insulin syringe scales and reconstitution arithmetic published at dosyne.com. CC BY 4.0, documented field semantics, no dosing data. Source: https://dosyne.com/api/ [Home](https://dosyne.com/)/Reference API # The syringe reference and the reconstitution arithmetic, as JSON Everything this site asserts about insulin syringes and reconstitution arithmetic is published as machine-readable JSON at `dosyne.com/api/v1/`. No key, no account, no rate limit, CORS open to any origin, licensed [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/) with attribution. It contains no dosing information, and it never will. ## What is here Dosyne publishes a narrow, checkable thing: the arithmetic that turns a vial strength and a volume of diluent into a number you can read off a barrel, and the instrument reference that arithmetic depends on. Those facts are rendered as prose on the reference pages, run as JavaScript in the five browser calculators, and served here as JSON. All three come from one module in the repository, and a build gate fails if the calculators and the published values disagree — so the page you read, the tool you use and the object you fetch cannot tell you three different things. *Public endpoints* | Endpoint | Returns | Use it for | | --- | --- | --- | | [`/api/v1/syringes.json`](https://dosyne.com/api/v1/syringes.json) | 3 calibrations, 3 barrel capacities, 2 diluents | Turning a reading into a volume, or a volume into a reading. | | [`/api/v1/formulas.json`](https://dosyne.com/api/v1/formulas.json) | 8 formulas, 5 readability thresholds, 5 calculators | Implementing the arithmetic, or checking an implementation against ours. | | [`/api/v1/library.json`](https://dosyne.com/api/v1/library.json) | Every page, with the query it answers and its markdown twin | Finding the source behind a figure, or a page to cite. | | [`/api/v1/apps.json`](https://dosyne.com/api/v1/apps.json) | A dated App Store snapshot of peptide and GLP-1 tracking apps | Comparing tracking apps. Published by one of them — see the disclosure in the payload. | | [`/api/v1/status.json`](https://dosyne.com/api/v1/status.json) | Generation timestamp and row counts | Deciding whether to refetch without pulling the payloads. | | [`/api/v1/openapi.json`](https://dosyne.com/api/v1/openapi.json) | OpenAPI 3.1 over all of the above | Generating a client. | There is also a machine index of the whole site at [/llms.txt](https://dosyne.com/llms.txt), the full text of the primary pages at [/llms-full.txt](https://dosyne.com/llms-full.txt), an RFC 9727 catalogue at [/.well-known/api-catalog](https://dosyne.com/.well-known/api-catalog), an ARD capability manifest at [/.well-known/ai-catalog.json](https://dosyne.com/.well-known/ai-catalog.json), four agent skills at [/.well-known/agent-skills/](https://dosyne.com/.well-known/agent-skills/index.json), and an account of what does and does not need authenticating at [/auth.md](https://dosyne.com/auth.md) (nothing does). Every page on this site also has a markdown copy: append `index.md` to any URL, or send `Accept: text/markdown`. ## The one fact the whole API encodes A syringe unit is a volume defined by the barrel. It is not a quantity of drug, and the barrel cannot know what it holds. One unit on a U-100 syringe is 0.01 mL of whatever is in it — insulin, saline, or a reconstituted peptide. One unit on a U-40 syringe is 0.025 mL. That is the entire difference between the two scales, and it is the reason a number of units, quoted without the concentration it was calculated at, is not an answer to anything. Almost every error this API exists to prevent is a version of forgetting that. A dosage chart printed in units with no concentration beside it cannot be applied to anyone else's vial. A calculator that hardcodes 100 is wrong on any other barrel. A conversion applied in the wrong direction produces a number that looks entirely reasonable. The data is shaped to make those mistakes hard: `ml_per_unit` and `units_per_ml` are both present so you never have to remember which way the division goes, every computed field carries the concentration it assumed, and every payload carries a `boundary` object saying what the figures are not. ## What implementers get backwards These are not edge cases. Each one produces a plausible wrong volume rather than an error, which is exactly why they survive code review. ### The direction of a scale conversion A coarser scale reads *fewer* marks for the same liquid, not more. 100 units on a U-100 barrel is 1 mL; the same 1 mL on a U-40 barrel is 40 units. The number 2.5 appears in the literature as the ratio between the volume of one U-40 mark and one U-100 mark, and it is very easy to reach for it when converting a reading — in which case the answer comes out 6.25 times too large. This site shipped exactly that in its own syringe visualiser: the "same volume on U-40" cell multiplied by 2.5 rather than by 40/100, so 20 units read as 50 instead of 8. It was corrected in September 2026, and the gate that would have caught it exists now. Convert through the volume — reading, then millilitres, then the other reading — and the direction cannot invert. ### Micrograms at the boundary Vials are labelled in milligrams. Amounts are usually discussed in micrograms. The factor of a thousand between them is the most common defect in a reconstitution calculator, and it is silent: a result a thousand times out still renders, still fits the field, and only looks wrong to someone who already knows the answer. Convert once, at the point where input enters the system, keep one unit internally, and label every field with the unit it is in. Every numeric field in this API carries its unit in its name for that reason. ### Concentration is required, and there is no sensible default There is no conversion from an amount to a syringe reading without a concentration. Not a difficult one, not an approximate one — it does not exist. An implementation that defaults the concentration when it is missing has invented a vial. If the caller has not supplied one, the correct response is to say so, which is what the calculators and the MCP tools here do. ### A graduation note is prose, not a number Barrel capacity is fixed by the scale: a 0.3 mL U-100 barrel reaches 30 units, a 0.5 mL one reaches 50, a 1 mL one reaches 100. The *graduation interval* — how far apart the printed lines are — is a property of the product and varies between manufacturers, which is why `graduation_note` is a sentence and not a figure. Do not synthesise a number from it. The only authority on the line spacing is the device in the reader's hand, and the correct advice is always to count the spaces between numbered marks rather than assume that every short line is one unit. ### Readability thresholds are not warnings about the arithmetic The `readability_thresholds` array describes the cases where the calculation is correct and the result is still unusable: a volume that will not fit one barrel, a reading too small to resolve by eye, a reading small enough that a one-mark error is a large proportional one, a concentration high enough that each mark carries a great deal. They are not error conditions and they do not mean a number is wrong. They mean a number needs a sentence beside it. An assistant that returns "0.8 units" without mentioning that no barrel displays that reading has answered precisely, and unhelpfully. ## Field semantics worth stating `units_per_ml` and `ml_per_unit` are reciprocals of each other and both are published deliberately. Multiply a volume by `units_per_ml` to get a reading; multiply a reading by `ml_per_unit` to get a volume. Storing only one of them is how a division ends up inverted three functions away from where it was written. `expression` on a formula is written to be read by a person and evaluated by a machine, with every symbol defined in the accompanying `variables` object and the unit of the result in `returns`. `worked` is one example carried from input to output. If your implementation disagrees with `worked`, your implementation is wrong — that is the field's entire purpose, and it is worth wiring into a test rather than reading once. `source` on every row is the page where the same claim is stated in prose with the reasoning behind it. It is the URL to cite. Nothing in this API is asserted that is not also asserted on a page a reader can check, which is the only way to guarantee the two cannot drift apart. `snapshot_date` on the app comparison is doing real work. Those figures are public App Store listing data taken on one day; ratings, versions and prices move afterwards, and the payload carries the date so a consumer can decide whether the snapshot is still worth quoting. The same payload carries a `disclosure` field, because the comparison is published by one of the apps in it. ## What this API does not contain Dosyne publishes arithmetic, not protocols. There is no endpoint here that returns an amount anyone should take, and there will not be one — not because the data would be hard to assemble, but because assembling it is the thing this publication exists to refuse. A JSON file of "typical peptide doses" would be the most requested object on this domain and the most harmful one to publish, since it would be applied by people with a different vial, a different concentration and no prescriber, and it would look authoritative while doing it. - What compound anyone should use. - What amount anyone should take, how often, or for how long. - Whether a plan someone describes is safe, correct or advisable. - Where to buy anything. This site names no vendor and links to none. What the API does answer is the part with a correct answer: - Arithmetic: concentration, volume, syringe units, how many draws a vial holds. - Instrument reference: what a mark on a given barrel is worth on a given scale. - Procedure mechanics: what reconstitution does, what a diluent is, how storage affects a solution. Four caveats travel with every figure, and they are in the `boundary` object of each payload rather than only in this documentation, because a retrieved JSON object travels alone exactly as a retrieved paragraph does. They are: that a syringe reading is a volume and says nothing about what is in the liquid; that the arithmetic cannot verify the vial's contents, sterility or actual concentration; that most research peptides are not approved by the FDA or EMA for human use and material sold for research use is not made to pharmaceutical standards; and that dosing decisions belong to a licensed prescriber. ## A worked request A 5 mg vial reconstituted with 2 mL of bacteriostatic water, drawn at 250 mcg. Fetch the scale factor, then do four divisions: ``` curl -s https://dosyne.com/api/v1/syringes.json | jq '.scales[] | select(.id=="U-100")' # { "id": "U-100", "units_per_ml": 100, "ml_per_unit": 0.01, ... } concentration = 5 mg / 2 mL = 2.5 mg/mL volume = 0.25 mg / 2.5 mg/mL = 0.1 mL reading = 0.1 mL * 100 = 10 units per unit = 2.5 mg/mL * 1000 * 0.01 = 25 mcg per mark draws = 5 mg / 0.25 mg = 20 ``` Ten units on a 1 mL barrel with two-unit lines is a comfortable reading; the same amount at a concentration four times higher would be 2.5 units, which is inside the proportionally-fragile threshold and is the kind of thing worth saying out loud. That is what the thresholds are for, and it is why the diluent volume — the one variable anybody actually chooses — is worth choosing deliberately rather than by habit. ## Caching, stability and fair use These are static files behind a CDN, served with a one-hour cache header. There is no rate limit beyond ordinary fair use, and no identity attached to a request. They are regenerated whenever the site is rebuilt; [status.json](https://dosyne.com/api/v1/status.json) carries a `generated_at` timestamp and the row counts, so a client can decide whether to refetch without pulling the payloads themselves. The `/api/v1/` prefix is a commitment. Fields will be added; existing fields will not change meaning or disappear inside v1, and a breaking change would appear at a new prefix. The syringe reference is a description of physical instruments and is not expected to change at all. ## Tools, not just files The same arithmetic is available as an MCP server at `https://dosyne.com/mcp` (Streamable HTTP, no authentication), described by [its server card](https://dosyne.com/.well-known/mcp/server-card.json). It exposes six read-only tools: reconstitute a vial, convert an amount to a reading, work out a diluent volume, look up a scale, lay out a titration schedule that was given to someone, and search the reference library. Each one returns the concentration it assumed and the page to cite alongside the figure. There is an A2A endpoint at `/a2a` over the same lookups, and the pages themselves register WebMCP tools for an assistant driving the browser. None of them can write anything, spend anything or read anything about a user. The Dosyne app keeps its log on the device with no account and no server, so there is no user data anywhere for an agent to reach — which is also why there is nothing here to authenticate. ## Reuse and attribution Everything under `/api/v1/` is licensed CC BY 4.0. Reuse it, including commercially, with a link back to [dosyne.com](https://dosyne.com/) or to the specific page a figure came from. If you build something on it we would like to know: [support@dosyne.com](mailto:support@dosyne.com). If you find a value here that disagrees with a page, that is a defect and we want the report — the two are generated from one source precisely so that cannot happen quietly. [Get the app](https://dosyne.com/get/) Free · no account · nothing leaves your phone --- HTML version: https://dosyne.com/api/ Structured data for this site: https://dosyne.com/api/v1/openapi.json · https://dosyne.com/llms.txt Dosyne publishes arithmetic, not protocols: nothing here is a dose recommendation, and dosing decisions belong to a licensed prescriber. Free to quote and reuse with a link back to the source URL above (CC BY 4.0). --- **About Dosyne — What We Publish and What We Refuse To** > Who builds Dosyne, why a site about peptide arithmetic sells no peptides, how we make money, and the editorial rules we hold ourselves to. Source: https://dosyne.com/about/ [Home](https://dosyne.com/)/About About # A calculator company that sells no compounds and prints no protocols. Dosyne is a reconstitution calculator and dose log for iPhone and Android, built by a small independent software team. We are not a clinic, a pharmacy, a compounding facility or a supplier, and we have no financial relationship with anyone who is. That matters more here than it would in most categories, and it is the first thing you should know about this publication. ## Why the conflict of interest matters Search for almost any question in this subject — how much bacteriostatic water to add, how to read a syringe, what a dosage chart means — and the pages that come back are published by companies selling the compounds being discussed. That is not a conspiracy. It is simply who had a commercial reason to write the page. But it has a consistent effect on the writing. A vendor page explains the mechanics cheerfully and stops just before the parts that would dampen a purchase: that most of these compounds are not approved for human use, that research-grade material is not made to pharmaceutical standards, that the published evidence for many of them is animal work, and that the confident cycle lengths circulating online are forum consensus rather than pharmacology. We can say all of that because we are not selling any of it, and saying it is most of the reason this site exists. ## What we publish Arithmetic, technique and reference material. Concentration and volume, unit conversion, syringe graduations, storage stability, injection-site rotation drawn from the decades of diabetes research that actually exists on the subject. These things have correct answers, they can be checked, and getting them wrong is how people are harmed — so we are exhaustive about them and we show the working rather than returning a number. ## What we refuse to publish No recommended amounts. No protocols. No cycle designs. No vendor links, no discount codes, no affiliate arrangements, and no sponsored placements of any kind. If a page here starts to read like a plan someone could follow, it has failed and we rewrite it. We refuse for a practical reason rather than a squeamish one. A dose decision requires knowing the person: their history, their other medications, what they are actually trying to achieve and whether any of this is appropriate at all. A website knows none of that, and a website that pretends otherwise is dangerous in a way a wrong calculator never is. So we do the part that generalises, and we are direct about where that part ends. ## How we make money, stated plainly The reconstitution calculator, the dose log and vial tracking are free in the app. A Pro subscription adds reminders, the cycle planner, injection-site history and weight progress. That subscription is the entire business model. This website carries no advertising and no affiliate links, and it never will while it covers this subject — the moment a page here earns a commission on something a reader buys, everything else on the site becomes harder to believe. ## Editorial rules We do not invent numbers. Where a figure would require a study we do not have, we describe the mechanism qualitatively instead of manufacturing a statistic. Where the evidence base is thin, we say it is thin rather than dressing up a plausible sentence as a finding. We show our working. Every calculator publishes the formula it uses so you can check the result by hand, and every reference table states the concentration it assumes, which is the exact thing whose absence makes most charts in this subject unusable. Our comparison pages name situations in which a competitor is the better choice, and mean them. Facts about other apps come from public store listing data on a stated date and from the developers' own descriptions; we do not speculate about features we cannot verify and we do not accuse anyone of anything. We correct errors visibly. In a subject where a decimal place matters, silently editing a page after somebody points out a mistake would be the wrong instinct. Write to [support@dosyne.com](mailto:support@dosyne.com) if you find one. ## How the app is actually built There is no server, no backend and no AI in Dosyne. The reconstitution engine is a few hundred lines of arithmetic running on your phone, exhaustively unit-tested before any screen was allowed to depend on it, and the tests are the reason we are willing to put a syringe drawing in front of you and say the plunger is where the answer is. The design decision we are most confident about is unglamorous: every logged dose stores the concentration in force at the moment it was recorded, alongside the compound name and the amount. It sounds like bookkeeping. It is the difference between a history that still means something in eight months and a column of numbers nobody can interpret, because the moment a vial is mixed differently, a bare milligram figure stops being enough to reconstruct what was actually administered. Most apps in this category do not do it, which is the single most useful thing we found while building the [comparison pages](https://dosyne.com/compare/). The second decision worth explaining is the refusal to sync. A dose history is sensitive enough that the safest place for it is one device with no copy anywhere else, including with us. That costs you cloud backup and multi-device access, and we would rather name the cost than quietly market the absence of a feature as a privacy benefit. ## Who this is for Three kinds of reader. Somebody who has been prescribed a GLP-1 medication and needs to turn a milligram figure into a number they can find on a barrel, reliably, at seven in the morning. Somebody mixing a research compound who wants the arithmetic checked and the honest state of the evidence rather than a vendor's enthusiasm. And somebody who simply wants a record they can hand to a clinician without reconstructing four months from memory. There is a fourth reader we are not trying to serve, and saying so saves time: if you want a protocol, a stack recommendation, a source, or a community telling you what works, this is the wrong site. We do not publish any of it and we are not going to start. ## What we are not We are not clinicians, pharmacists or pharmacologists, and we do not present ourselves as any of those. The material here is written carefully, sourced from public references, and built by people who had to understand this subject well enough to implement it correctly in software — which is a real form of understanding and also a bounded one. Where a question is genuinely clinical, we say so and point at the person who should answer it. If you have professional expertise here and something on this site is wrong, we would genuinely like the correction. ## Privacy, briefly The app has no account, no server and no analytics. Your logs live on your device and nowhere else, and the App Store label reads Data Not Collected because that is literally true. The calculators on this site run in your browser and never transmit what you type. The trade-off is real — there is no cloud backup, and we cannot recover a lost history — and we would rather accept that than hold a database of what people inject. The detail is in the [privacy policy](https://dosyne.com/privacy/). ## Why the site is called The Lab and not The Blog A small naming decision that reflects an editorial one. A blog implies opinion, frequency and personality. What this section actually contains is reference material — pages meant to be returned to, checked against, and quoted, rather than read once in a feed. Several of them exist because we needed them ourselves while building the engine and could not find a version on the open web we trusted enough to link to instead. That also sets the standard for whether something gets published. The test is not whether a topic would attract traffic; it is whether we can say something true and specific that the pages currently ranking do not. Where the honest answer is that the existing material is already good, we would rather link to it than manufacture a competing page. That happens less often in this subject than it should. ## Where to start If you have a vial in front of you, the [reconstitution calculator](https://dosyne.com/tools/peptide-reconstitution-calculator/) is the fastest route and it shows every intermediate number. If you are trying to decide how much diluent to use, the [bacteriostatic water calculator](https://dosyne.com/tools/bacteriostatic-water-calculator/) solves it in both directions. If you want to understand the subject rather than compute one answer, start with [how to read an insulin syringe](https://dosyne.com/lab/read-an-insulin-syringe/), which corrects the misunderstanding underneath most of the serious errors in this field, then [why most peptide dosage charts are unusable](https://dosyne.com/lab/peptide-dosage-charts/) — the piece that will make you distrust most of what else you find, for reasons we set out in full. ### The app Free on iPhone and Android. Calculator, dose log and vial tracking at no cost, no account required. [Get the app](https://dosyne.com/get/) Free · no account · nothing leaves your phone --- HTML version: https://dosyne.com/about/ Structured data for this site: https://dosyne.com/api/v1/openapi.json · https://dosyne.com/llms.txt Dosyne publishes arithmetic, not protocols: nothing here is a dose recommendation, and dosing decisions belong to a licensed prescriber. Free to quote and reuse with a link back to the source URL above (CC BY 4.0). --- **Contact & Subscription Help | Dosyne** > One email address for everything, plus step-by-step instructions for cancelling a Dosyne subscription on iPhone or Android and requesting a refund. Source: https://dosyne.com/contact/ [Home](https://dosyne.com/)/Contact # Contact **support@dosyne.com** One address for everything — bugs, refunds, corrections, data questions, or telling us a calculator is wrong. A person reads it, usually within two working days. [Write to us →](mailto:support@dosyne.com) There is no contact form and no ticket number. Email is faster for both of us and you keep a copy of what you sent. One thing we cannot help with, stated first so nobody wastes a message: we do not advise on what to take, how much, or whether a compound is suitable for you. Not because we are being cautious for its own sake, but because answering would require knowing your medical history, and the person who has that is your prescriber. ## Cancelling a subscription Subscriptions are billed by the app store rather than by us, so we cannot cancel one on your behalf even when we would like to. You can do it in under a minute. Cancelling during a free trial costs nothing, and cancelling later stops the next renewal while leaving Pro features active until the end of the period you have already paid for. How to cancel on iPhone or iPad 1. Open the Settings app. 2. Tap your name at the top of the screen. 3. Tap Subscriptions. On older iOS versions it sits under Media & Purchases, then View Account, then Subscriptions. 4. Tap Dosyne in the list of active subscriptions. 5. Tap Cancel Subscription and confirm. During a trial the same button reads Cancel Free Trial. If Dosyne is not in the list, the subscription has either already been cancelled or was bought with a different Apple ID than the one now signed in. You can also reach the same screen from the App Store app by tapping your profile picture and choosing Subscriptions. How to cancel on Android 1. Open the Google Play Store app. 2. Tap your profile icon in the top right. 3. Tap Payments & subscriptions, then Subscriptions. 4. Select Dosyne. 5. Tap Cancel subscription and follow the prompts. If you subscribed on an Android device but the subscription does not appear, check that you are signed into the same Google account that made the purchase. A subscription bought on iOS cannot be cancelled from an Android device and the reverse is also true — each store manages only its own. How to request a refund 1. On Apple: go to reportaproblem.apple.com, sign in, find the Dosyne purchase, choose Request a refund and give a reason. 2. On Google: open Play Store, go to Payments & subscriptions, then Budget & order history, select the purchase and choose Report a problem. Both stores decide refunds under their own policies and we have no ability to approve or reject one. If you were charged unexpectedly — a trial you thought you had cancelled, or a renewal you did not expect — email us anyway. We cannot move the money, but we can confirm what the app's records show, and that has helped people make their case. Restoring a purchase on a new device Open Dosyne, go to Settings inside the app and choose Restore Purchases. Because there is no account, entitlement travels with the store account that bought it, so sign in with the same Apple ID or Google account. Note that a purchase does not transfer between platforms: an iOS subscription does not unlock the Android app. ## Your data does not move with you This surprises people, so it is worth saying clearly here as well as in the privacy policy. Dosyne has no account and no server, which means your dose history lives on that device and nowhere else. It does not sync to a new phone by itself, and we cannot recover it for you, because we never had it. Before changing or resetting a device, use the export function in Settings and keep the file somewhere you control. If you have already lost a device without an export or a system backup, that history is gone and there is nothing we can retrieve. We would rather tell you this on a page you might read beforehand than in a reply afterwards. ## Before you email: three things worth checking Most of the messages we receive resolve to one of three things, and checking them yourself is faster than waiting for a reply. The first is a result that looks wrong by a factor of ten or a thousand. Almost every time, this is a milligram entered where micrograms were expected or the reverse. One milligram is one thousand micrograms, and the decimal error is easy to make and hard to see. Re-enter the amount and check which unit the field is asking for; the calculators label it explicitly for exactly this reason. The second is a syringe reading that disagrees with a chart you found elsewhere. That is usually not an error in either place: the chart assumed a concentration it did not print, and yours is different. Run the numbers through the [mcg to units converter](https://dosyne.com/tools/mcg-to-units-converter/) at both concentrations and the gap will usually explain itself. We take this apart properly in [why most peptide dosage charts are unusable](https://dosyne.com/lab/peptide-dosage-charts/). The third is reminders not arriving. Check that notification permission is granted for Dosyne in your system settings, that a Focus or Do Not Disturb mode is not silencing them, and that Low Power Mode is off. Reminders are scheduled locally by the device, so if the operating system suppresses them there is nothing on our side that can override it. ## Reporting a bug The useful report says what you expected, what happened instead, and enough for us to reproduce it. For Dosyne the details that help most are your operating system version, your device model, the app version from the Settings screen, and the exact numbers you entered when something looked wrong. Screenshots are welcome. A couple of sentences is plenty. Arithmetic complaints get priority over everything else in the queue. If a calculator gives an answer you believe is wrong, send the inputs and the output you saw. Sometimes the answer is that a chart you were comparing against assumed a different concentration, which is itself worth knowing. Sometimes it is our bug, and in that case we want it today. ## Feature requests Send them. We keep a list and a fair amount of what has shipped came from it. The most useful request describes the situation rather than the solution: telling us that you lost track of which vial a dose came from is more actionable than telling us to add a field, because the field might not be the right fix. We will be honest when the answer is no. Cloud sync is the most requested feature and we have deliberately not built it, because a synced dose history means a database of what people inject, held by us, and we do not want to be the custodian of that. That position may look stubborn from the outside. It is the same reasoning that produced the Data Not Collected label, and we would rather keep both than trade one for convenience. ## Corrections If something we publish is wrong — an article, a calculator, or a claim on a comparison page — tell us what is wrong and, where you can, what the correct version is. We fix errors and note that a page has been corrected rather than editing silently. Developers of the apps we compare ourselves against are especially welcome to write in; if we have described your app unfairly or out of date, we will fix it. ## Data and privacy requests Requests to access or delete data go to the same address. In practice there is almost nothing to request: the app has no accounts and stores everything on your device, so deleting an entry deletes it and deleting the app deletes all of it. The full detail is in the [privacy policy](https://dosyne.com/privacy/), which is written to be read rather than survived. ## Press and other enquiries Same address. We are happy to answer questions about how the calculators work, why the app has no server, or what we found while researching the reference material — that research is public and we have no reason to be precious about it. We do not accept sponsored content, paid reviews, guest posts or link placements, and enquiries about those will get a short no rather than a negotiation. ## Accessibility If something on this site or in the app fails with a screen reader, at a larger text size, or with reduced motion enabled, that is a bug and we want the report. The syringe drawing in particular carries meaning visually, so if the numeric readouts beside it are not conveying the same information to you, tell us and we will fix it. ## What happens to your email It goes to a mailbox a person reads. We do not run it through a support platform, we do not add you to a mailing list, and we use the address only to reply. If your message leads to a change, we will tell you when it ships instead of leaving you wondering. If we cannot help, we will say so plainly rather than going quiet. We reply in English; if that is not comfortable, write in your own language and we will manage. --- HTML version: https://dosyne.com/contact/ Structured data for this site: https://dosyne.com/api/v1/openapi.json · https://dosyne.com/llms.txt Dosyne publishes arithmetic, not protocols: nothing here is a dose recommendation, and dosing decisions belong to a licensed prescriber. Free to quote and reuse with a link back to the source URL above (CC BY 4.0). --- **Privacy Policy | Dosyne** > How the Dosyne peptide calculator app and dosyne.com handle data: why there is no account and no server, what stays on your device, and what we never collect. Source: https://dosyne.com/privacy/ · updated: 2026-07-31 [Home](https://dosyne.com/)/Privacy # Privacy policy This covers the Dosyne mobile app and the website at dosyne.com. It is short for an unusual reason: the app has no account, no server and no analytics, so there is very little to describe. Last updated 31 July 2026 ## Who we are Dosyne is published by Vast Flow, LLP, which operates the app and this website and is the data controller for the limited processing described here. Write to [support@dosyne.com](mailto:support@dosyne.com) with any question about this policy, including a request to access or delete data. ## The short version Dosyne has no user accounts, no sign-in and no cloud sync. It never asks for your name, your email address or your date of birth, and there is nowhere for it to send them. All of your data — logged doses, vials, injection sites, weights, settings — lives in the app's own storage on your device. Every calculation happens locally. Deleting the app deletes the data with it. This is why the App Store privacy label reads Data Not Collected. That is not a formality we squeezed through; it is a genuine description of the architecture. ## Why we built it this way A record of what someone injected, when, and where on their body is about as sensitive as health data gets. It could be subpoenaed, breached, sold in an acquisition, or simply mishandled. The most reliable protection against all of those is not to hold it, so the app has no server that could be compromised and no database that could be breached. The cost is real: there is no cloud backup and no sync between your phone and your tablet. We think that trade is the right one for this category, and we would rather state the cost than pretend it does not exist. ## What the app stores on your device Logged doses with the compound name, amount and concentration at the time; vials and their remaining volume; injection-site history; weight entries; cycle plans; reminder settings; and non-sensitive preference flags. None of it is transmitted. It may be included in your own device backup if you have that enabled, in which case it is governed by Apple's or Google's terms rather than ours. ## Apple Health With your permission, the app reads body mass from Apple Health for the progress chart and mirrors weights you enter manually back into Health. That exchange is local to the device and governed by Apple's HealthKit rules, which prohibit using health data for advertising. We never receive it. You can refuse the permission and the app works normally without it, minus the chart. Note that iOS deliberately hides read-permission status from apps, so what we show you is our own intent rather than a confirmed connection. ## Notifications Reminders are scheduled locally by your device. There is no push server, no token, and nothing leaves the phone to make a reminder fire. Reminder text never contains an amount or a compound name, so a notification on a lock screen does not disclose anything to somebody glancing at it. ## Purchases Subscriptions are sold and processed by Apple and Google. We never see your payment details. To decide whether to unlock Pro features, the app uses RevenueCat, which processes an anonymous identifier and the receipt the store issues. That tells us a subscription exists and what state it is in. It does not identify you, and we cannot connect a subscription to a person or to any logged data. ## Analytics: none in the app The app contains no analytics SDK. No Firebase Analytics, no Crashlytics, no attribution SDK, no event tracking, no advertising identifier. We do not know which screens you open, which compounds you log, or how often you use it. This costs us product insight and we accept that. This website is different and you should know it. It loads Microsoft Clarity, which records aggregate site usage — pages viewed, approximate region, device and browser, and anonymised interaction patterns such as scroll depth — so we can find pages that are broken or confusing. It is not connected to any app data and it does not follow you to other sites. It sets cookies and honours the Global Privacy Control signal where your browser sends one. A content blocker will stop it and every calculator on this site works normally without it. ## The calculators on this site Everything you type into a calculator here stays in your browser. Vial strengths, diluent volumes and amounts are never transmitted to us, because the arithmetic runs on your machine in JavaScript. Closing the tab discards it. There is no form submission anywhere on this website. ## What we never collect We do not collect your name, email address, contacts, photos, precise location, advertising identifier, or any health data. We do not sell data, we do not share it with data brokers, and there is no advertising in the app. There is no mechanism by which we could build a profile of an individual user, because there is no identity to attach one to. ## Legal bases, for readers in the EEA and UK Because the app processes personal data on the device rather than transmitting it to us, most of it never becomes processing we perform. Purchase-receipt validation is necessary to perform the contract you entered into when subscribing. Website analytics rest on our legitimate interest in improving a free resource, balanced against the fact that they do not identify you. ## Retention App data is retained on your device until you delete it or delete the app. We hold no copy and cannot retrieve or restore it — if you delete the app without a device backup, that history is gone, and we mention it here because people are sometimes surprised. Purchase records are retained for as long as store receipt validation requires. Website analytics follow Microsoft Clarity's own retention schedule. ## Your rights You may have the right to access, correct, delete or port your personal data, and to object to certain processing. In practice these are satisfied by the app itself: deleting an entry deletes it, and deleting the app deletes everything. If you want written confirmation of what we hold — which for an app user is a purchase receipt state and nothing more — write to [support@dosyne.com](mailto:support@dosyne.com) and we will respond within thirty days. ## Children Dosyne is not directed at children and we do not knowingly collect data from anyone under 13. Given the subject matter, the app is intended for adults. ## Security The strongest security property of this app is architectural: there is no account to compromise, no password to steal, no server to breach and no central database of user records to leak. Data on your device is protected by the operating system's own storage protections and by your device passcode. Website traffic is served over an encrypted connection. ## International transfers We hold no user data to transfer. Apple, Google, RevenueCat and Microsoft process data in the regions described in their own policies, which may include the United States, under the transfer mechanisms those providers publish. ## Changes If the way data is handled changes, this page changes and the date at the top changes with it. Material changes will also be announced in the app. If we ever added a server component, we would say so prominently rather than quietly amending a clause here. ## Cookies and similar technologies The app uses no cookies; it is not a browser. On this website the only cookies set are those used by Microsoft Clarity for the aggregate analytics described above. There is no advertising cookie, no remarketing pixel, no social login and no embedded third-party widget that could set one. The calculators store nothing in your browser beyond what the page needs while it is open, so closing the tab discards everything you entered. We honour the Global Privacy Control signal where your browser sends one, and a content blocker or your browser's built-in tracking protection will prevent the analytics script loading at all. Every calculator on this site works normally without it. ## If you are in California We do not sell personal information and we do not share it for cross-context behavioural advertising as those terms are defined in the California Consumer Privacy Act. There is no advertising in the app at all. You have the right to know what we hold, to request deletion, and not to be discriminated against for exercising either — and because there is no account, exercising them usually requires nothing more than deleting the app. ## A note on sensitive categories A record of injections is sensitive personal data under several privacy regimes, and in some jurisdictions it attracts specific protections. The design answer we chose is the strongest one available: we do not receive it. Because the data never leaves your device, we hold no special category data about any user, we cannot be compelled to produce it, and no breach of our systems could expose it. If that ever changed we would say so prominently rather than amending a clause on this page. ## Contact Questions, deletion requests and complaints go to [support@dosyne.com](mailto:support@dosyne.com). If you are in the EEA or the UK and are not satisfied with our response, you may complain to your national data protection authority. --- HTML version: https://dosyne.com/privacy/ Structured data for this site: https://dosyne.com/api/v1/openapi.json · https://dosyne.com/llms.txt Dosyne publishes arithmetic, not protocols: nothing here is a dose recommendation, and dosing decisions belong to a licensed prescriber. Free to quote and reuse with a link back to the source URL above (CC BY 4.0). --- **Terms of Use | Dosyne** > Terms covering the Dosyne peptide calculator app and dosyne.com — what the calculators are for, what they are not, subscriptions, cancellation and liability. Source: https://dosyne.com/terms/ · updated: 2026-07-31 [Home](https://dosyne.com/)/Terms # Terms of use These terms cover the Dosyne mobile app and the website at dosyne.com. The most important clause is the third one, and we have put it near the top rather than burying it where terms usually hide the part that matters. Last updated 31 July 2026 ## Who you are contracting with Dosyne is operated by Vast Flow, LLP. "We", "us" and "our" mean Vast Flow, LLP. "The app" means the Dosyne mobile application on iOS and Android. "The site" means dosyne.com, including the free calculators published on it. ## What we provide A calculator and a record-keeping tool, plus written reference material about the arithmetic and handling involved in reconstituting a lyophilised compound. That is the entire scope of the service. ## This is not medical advice, and it is not a prescription Nothing in the app or on the site is medical advice, a diagnosis, a prescription, or a recommendation to use any substance. We do not tell you what to take, how much, how often, or for how long, and we will not do so if you ask. Those decisions belong to a licensed prescriber who knows your history. The calculators perform arithmetic on numbers you supply. They cannot verify that a vial contains what its label claims, that it is sterile, that it is pure, or that any of it should be administered to a person. A correct calculation performed on wrong inputs produces a confidently wrong answer, and the responsibility for the inputs, and for the decision to act on any output, is yours. We also state plainly, because it is true and because most pages in this subject do not: most research peptides are not approved by the FDA or the EMA for human use. Material sold as research-use-only is not manufactured to pharmaceutical standards simply because that phrase appears on a label, and purity, sterility, identity and actual content are not guaranteed. ## What we will not publish We do not publish dosing protocols, recommended amounts, cycle designs, or links to vendors, and we do not accept payment to do so. If you have arrived looking for those, this is the wrong site, and that is deliberate rather than an oversight. ## Free tools on this site The calculators are provided free and without warranty of any kind. Everything you type stays in your browser and is never transmitted to us. We have tested the arithmetic and we publish the formulas so you can check it, and you should: if a result looks wrong, it may be, and we would like to hear about it. ## Your records Data you enter into the app is stored on your device and nowhere else. We hold no copy, which means we cannot restore your history if you delete the app, lose the device, or reset it without a backup. Keeping a backup is your responsibility, and the app's export function exists for that purpose. ## Subscriptions and billing The reconstitution calculator, the dose log and vial tracking are free. A Pro subscription costs $5.99 weekly or $49.99 yearly with a 7-day free trial on the yearly plan. Prices displayed in the app are set in App Store Connect and Google Play Console and are authoritative; prices on this website are informational and may lag a change or differ by region and currency. Subscriptions are sold and processed by Apple or Google. Payment is charged at confirmation of purchase and renews automatically unless auto-renew is turned off at least 24 hours before the end of the current period. If a free trial is offered and you subscribe to the same plan before it ends, the unused portion is forfeited, which is the store's rule rather than ours. ## Cancelling Cancel at any time in your Apple or Google account settings. Cancelling during a free trial costs nothing. Cancellation takes effect at the end of the current billing period and you keep Pro features until then. We cannot cancel on your behalf because we do not control the billing relationship. Step-by-step instructions for both platforms are on the [contact page](https://dosyne.com/contact/). ## Refunds Refunds are handled by Apple and Google under their own policies and requests go through them. If you were charged in error, contact us as well — we cannot move the money, but we can support your request, and we will. ## Acceptable use Use the app and the site for their intended purpose. Do not attempt to disrupt them, do not scrape the site at a volume that degrades it for others, and do not redistribute the calculators as your own product. You may quote and link to anything we publish, and we would prefer that to an inaccurate paraphrase. ## Intellectual property The app, the site design, the written articles and the calculators are our intellectual property. Third-party names and trademarks appearing on this site, including the names of other apps on the comparison pages and the generic and brand names of medicines referred to descriptively, belong to their respective owners. Their appearance does not imply affiliation with or endorsement by those owners, and nothing here should be read as a claim to be associated with any pharmaceutical manufacturer. ## Accuracy and corrections We aim to be accurate and we will sometimes be wrong. If you find an error in an article, a calculator or a comparison page, write to [support@dosyne.com](mailto:support@dosyne.com). We correct mistakes and we say that we have rather than editing silently. In a subject where an arithmetic error can matter, this is not a courtesy but a duty. ## Feedback If you send a suggestion or a feature idea, we may act on it without owing compensation or attribution. That exists because good ideas frequently arrive from several users independently and we cannot run a product where implementing an obvious improvement creates a claim. If you want to send something you consider confidential, tell us before you send it. ## Availability and changes to the service We may change, suspend or discontinue any part of the app or the site, including individual features and individual free calculators. We have no plan to remove any of the free calculators and we will not put an existing free one behind a paywall. ## Third-party services The app and site depend on services we do not control, including Apple and Google for distribution and billing and the providers named in the [privacy policy](https://dosyne.com/privacy/). Their terms apply to their services. We are not responsible for the content or practices of any third-party site we link to. ## Limitation of liability To the fullest extent permitted by law, we are not liable for indirect or consequential loss arising from use of the app or the site, including any loss arising from reliance on a calculation, from data lost when an app is deleted, or from any decision made about a substance. Where liability cannot be excluded, it is limited to the amount you have paid us in the twelve months before the claim, which for most users is zero. Nothing here limits liability for death or personal injury caused by our negligence, or for fraud, where such limitation is not permitted by law. ## Severability, waiver and assignment If a provision is unenforceable it is limited or removed to the minimum extent necessary and the rest stands. Not enforcing a provision once is not a waiver of it. You may not transfer your rights without our consent; we may assign ours as part of a merger, acquisition or sale of assets, on notice. With the privacy policy, these terms are the entire agreement between us about the app and the site. ## Termination Stop using the app at any time by deleting it. We may suspend access if the acceptable-use terms are breached in a way that harms the service or other users. Ending your use does not entitle you to a refund of a period already paid for, which remains subject to the store's policy. ## Age The app is intended for adults. You must be old enough to form a binding contract where you live in order to subscribe, and where you are under the age of majority a parent or guardian must agree to these terms on your behalf. Given the subject matter, we do not market the app to anyone under 18. ## Export and portability The app can export your log as a file you keep. That export is the only route by which your data leaves the device, it happens through your own share sheet, and where it goes after that is under your control rather than ours. We recommend using it before changing devices, because we hold no copy and cannot restore anything. ## Availability and changes to the service We may change, suspend or discontinue any part of the app or the site. We have no plan to remove any of the free calculators and we will not move an existing free one behind a paywall. If a paid feature were discontinued during a subscription period we would say so in the app, and the store's refund process remains open to you. ## Governing law These terms are governed by the laws applicable to Vast Flow, LLP's place of establishment. If you are a consumer, this does not deprive you of the protection of the mandatory consumer law of your country of residence. ## Contact Anything about these terms goes to [support@dosyne.com](mailto:support@dosyne.com). --- HTML version: https://dosyne.com/terms/ Structured data for this site: https://dosyne.com/api/v1/openapi.json · https://dosyne.com/llms.txt Dosyne publishes arithmetic, not protocols: nothing here is a dose recommendation, and dosing decisions belong to a licensed prescriber. Free to quote and reuse with a link back to the source URL above (CC BY 4.0).