Peptide calculator: dosage, reconstitution and syringe units
Reconstitute peptides precisely, then never do the math again. Enter your vial, BAC water and dose to get the exact units to draw, with every step of the formula shown, and save the protocol in the PepSync app.
- Free, no sign-up
- Formula shown below
- U-100 syringe units
The PepSync app
Track every peptide dose in one place.
Save your peptides, mixes and schedule, and get a reminder when each dose is due.
- Saved calculationsEvery vial and dose one tap away. No more screenshots.
- Schedules & remindersDaily, weekly or custom. Get a nudge when it’s time.
- Titration plansStep your dose up over weeks with the draw worked out for each step.
- Dose logSee what you took and when, and how much is left in the vial.
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- calculations run
- 428,000+
- peptides supported
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How your peptide draw is calculated
- 1Find the concentration
5 mg × 1,000 ÷ 2 mL
= 2,500 mcg/mL - 2Work out the volume
250 mcg ÷ 2,500 mcg/mL
= 0.10 mL - 3Convert to units
0.10 mL × 100
= 10 units
On a U-100 insulin syringe, 100 units equals 1 mL, so each unit is 0.01 mL. The 0.3 mL (30 unit) and 0.5 mL (50 unit) syringes use the same scale, just shorter, which makes small doses easier to read.
Peptide calculator reference
Peptide reconstitution chart
How many units each dose takes for the most common vial and BAC water set-ups, then the usual mix for the most-used peptides. Use the calculator above for your own vial.
Units per dose by vial and BAC water
| Dose | 5 mg + 2 mL2.5 mg/mL | 10 mg + 2 mL5 mg/mL | 10 mg + 3 mL3.33 mg/mL | 15 mg + 3 mL5 mg/mL | 20 mg + 2 mL10 mg/mL |
|---|---|---|---|---|---|
| 100 mcg | 4 u(0.04 mL)50 per vial | 2 u(0.02 mL)100 per vial | 3 u(0.03 mL)100 per vial | 2 u(0.02 mL)150 per vial | 1 u(0.01 mL)200 per vial |
| 250 mcg | 10 u(0.1 mL)20 per vial | 5 u(0.05 mL)40 per vial | 7.5 u(0.08 mL)40 per vial | 5 u(0.05 mL)60 per vial | 2.5 u(0.03 mL)80 per vial |
| 500 mcg | 20 u(0.2 mL)10 per vial | 10 u(0.1 mL)20 per vial | 15 u(0.15 mL)20 per vial | 10 u(0.1 mL)30 per vial | 5 u(0.05 mL)40 per vial |
| 1 mg | 40 u(0.4 mL)5 per vial | 20 u(0.2 mL)10 per vial | 30 u(0.3 mL)10 per vial | 20 u(0.2 mL)15 per vial | 10 u(0.1 mL)20 per vial |
| 2.5 mg | 100 u(1 mL)2 per vial | 50 u(0.5 mL)4 per vial | 75 u(0.75 mL)4 per vial | 50 u(0.5 mL)6 per vial | 25 u(0.25 mL)8 per vial |
Swipe the table to see every vial →
Educational reference only — not a dose recommendation. Units assume a U-100 insulin syringe (100 units = 1 mL on U-100); “per vial” is how many of that dose the vial holds, before the small dead-space loss on each draw. Confirm against your own vial label, diluent, and clinician or pharmacy instructions.
Quick reference: 12 popular peptides
| Peptide | Common vial | BAC water | Strength | Example dose | U-100 units |
|---|---|---|---|---|---|
| Retatrutide calculator | 10 mg | 2 mL | 5 mg/mL | 2 mg | 40 u |
| Tirzepatide calculator | 10 mg | 2 mL | 5 mg/mL | 2.5 mg | 50 u |
| Semaglutide calculator | 5 mg | 2 mL | 2.5 mg/mL | 250 mcg | 10 u |
| GHK-Cu calculator | 50 mg | 5 mL | 10 mg/mL | 2 mg | 20 u |
| BPC-157 calculator | 5 mg | 2 mL | 2.5 mg/mL | 250 mcg | 10 u |
| MOTS-c calculator | 10 mg | 2 mL | 5 mg/mL | 5 mg | 100 u |
| TB-500 calculator | 5 mg | 2 mL | 2.5 mg/mL | 2.5 mg | 100 u |
| Melanotan II calculator | 10 mg | 2 mL | 5 mg/mL | 250 mcg | 5 u |
| PT-141 calculator | 10 mg | 2 mL | 5 mg/mL | 1.75 mg | 35 u |
| Tesamorelin calculator | 5 mg | 2 mL | 2.5 mg/mL | 1 mg | 40 u |
| NAD+ calculator | 500 mg | 5 mL | 100 mg/mL | 50 mg | 50 u |
Swipe the table to see every column →
Example set-ups for the maths, not dose recommendations. Not sure how much water to add? Use the peptide reconstitution calculator.
Peptide calculators
Dedicated calculators for high-intent protocols.
Peptide-specific pages with presets, worked examples, and FAQ for the most-asked compounds.
- SESemaglutide calculatorGLP-1 · GLP-1 receptor agonist
- TITirzepatide calculatorGLP-1 · GLP-1 / GIP agonist
- BPBPC-157 calculatorRecovery · Recovery peptide
- RERetatrutide calculatorGLP-1 · GLP-1 / GIP / glucagon agonist
- TBTB-500 calculatorRecovery · Recovery peptide
- IPIpamorelin calculatorGrowth · Growth-hormone secretagogue
- MOMOTS-c calculatorLongevity · Mitochondrial peptide
- EPEpithalon calculatorLongevity · Telomere-research peptide
- SESemax calculatorCognitive · Nootropic peptide
The PepSync app
Your peptide protocol, in your pocket.
The web calculator gets you a number. The app gets you results, month after month, vial after vial.
- Save unlimited protocolsEach calculation becomes a reusable protocol — vial, water, dose, syringe, schedule. Auto-recalls every detail.
- Smart dose remindersNotifications that know your cycle. Snooze, skip, or log — tracking takes one tap.
- Track sites and cyclesRotate injection sites automatically. See cycle length, vial usage, and per-dose cost trend over time.
- Private by designYour protocols never leave your device unless you opt in. End-to-end encrypted sync, full export anytime.
Get the app — it’s freeFree to download · No CC required
Manual vs PepSync
Stop running your protocol on memory.
A free calculator is a great start. PepSync is the rest of the protocol.
Doing it manuallyPepSync
- Reconstitution mathManually: Manual conversions, calculator appWith PepSync: Auto-calculated, saved per peptide
- Dose remindersManually: Phone alarms, sticky notesWith PepSync: Smart notifications by protocol
- Injection site rotationManually: Mental notesWith PepSync: Auto-rotated, visualized
- Cycle trackingManually: Spreadsheet (if you remember)With PepSync: Full timeline, exportable
- Cost per doseManually: GuessworkWith PepSync: Tracked to the cent
- Sharing with providerManually: ScreenshotsWith PepSync: One-click PDF report
Core tools
Start with the broad calculator tools.
Use the generic calculators for reconstitution, dose volume, and concentration checks before moving into peptide-specific pages.
- Peptide reconstitution calculatorFree peptide reconstitution calculator: how much BAC water to add for any vial, then concentration, draw volume and U-100 syringe units for your dose. Includes mixing steps and how long mixed peptides last.
- Peptide dose calculatorPeptide dose volume calculator: convert a known concentration and target dose into mL and syringe units for U-100, U-50 and U-40 syringes. For a full vial set-up, use the peptide calculator.
- Peptide concentration calculatorCalculate peptide concentration in mg/mL or mcg/mL from vial amount and diluent volume before converting doses.
- Peptide blend calculatorFree peptide blend calculator and peptide calculator for blends: enter total mg, BAC water, and target dose to get concentration, draw volume, and syringe units for combined vials like CJC-1295 / Ipamorelin.
- HGH reconstitution calculatorFree HGH IU calculator: enter the vial's IU, your BAC water and your dose in IU to get IU per mL, the draw volume and U-100 syringe units, with the 3 IU = 1 mg conversion and charts for 10, 36 and 100 IU.
- HCG reconstitution calculatorFree HCG reconstitution calculator for 5,000 and 10,000 IU vials: enter the IU, the water you add and your dose in IU to get IU per mL, the draw volume and U-100 syringe units. Not a pregnancy hCG level calculator.
“Saved my Sunday morning. Used to redo this math every single vial. Now my phone just reminds me.”
“The injection-site rotation alone is worth it. I was double-dosing the same spot for weeks before.”
“Finally a calculator that gets U-50 syringes right. I send every new patient here before their first injection. The result screen is gorgeous.”
Latest guides
Read up before you reconstitute.
Plain-English walkthroughs on reconstitution, storage, syringes, and dosing — written so you get it right the first time.
- ReconstitutionHow to reconstitute peptides correctlyHow to reconstitute peptides step by step: how much bacteriostatic water to add, how to add it without damaging the powder, then concentration, storage and the mistakes to avoid.Updated Oct 8 · 10 min read
- SuppliesWhat is bacteriostatic water?Understand BAC water, sterile water, preservative differences, multi-dose vial handling, and when to follow specific diluent instructions.Updated Oct 8 · 7 min read
- ProtocolsHow to think about peptide stacksA cautious guide to organizing multiple peptide protocols, schedules, vial math, and tracking without turning stack pages into medical claims.Updated Jul 21 · 8 min read
Common questions
Things people ask before they start.
Answers to the questions we hear most about reconstitution, dosing, and how PepSync handles your protocols.
How do I use a peptide calculator?
Enter the peptide in the vial (mg), the bacteriostatic water you added (mL) and your dose (mcg or mg). The calculator divides the vial by the water to get the strength, divides your dose by that to get the mL, and converts mL to units on your insulin syringe (100 units = 1 mL on U-100).
How many units is 250 mcg on an insulin syringe?
It depends on the mix. With a 5 mg vial in 2 mL (2.5 mg/mL), 250 mcg is 0.1 mL — 10 units on a U-100 syringe. With a 10 mg vial in 2 mL (5 mg/mL) it is 5 units, and with a 10 mg vial in 3 mL it is 7.5 units.
How much bacteriostatic water should I add to a peptide vial?
Usually 1 to 3 mL, chosen so your dose lands on a readable mark. The water doesn't change the dose, only how many units it takes: more water makes small doses easier to measure. The reconstitution calculator works out the exact volume for the units you want.
Is this calculator accurate?
Yes. The math is the same volumetric formula clinics use: dose ÷ concentration = mL to draw. We've cross-checked against published protocols for 60+ peptides. That said, verify with a clinician before you inject.
What's the difference between U-100, U-50 and U-40 syringes?
Insulin syringes are graduated in units, not mL. A U-100 syringe has 100 units per mL. U-50 has 50, U-40 has 40.
Do you save my calculations?
Not on this website. The web calculator is fully client-side. The PepSync app does save your protocols on-device with optional encrypted sync.
Is PepSync free?
The web calculator is 100% free. The mobile app has a free tier and a Pro tier for unlimited protocols, site rotation, cost tracking, and reports.
Are peptides legal?
Therapeutic use varies by jurisdiction. We don't sell peptides; we help you calculate doses for whatever protocol your provider has prescribed.
Can I export my data?
Yes. PepSync is designed around data ownership, including export options for your protocols and history.
From PepSync users
Dosing with confidence.
“Very good and accurate… shows you a diagram of where to pin. Very easy to use and very beginner friendly if you’re starting off.”
jesaiah685 · App Store review · Australia “User friendly. Easy to navigate and understand.”
jusPeaches · App Store review · United States “Well put together. Nice friendly layout.”
Crowleyboy666 · App Store review · United Kingdom
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