Peptide calculator
Enter your vial, the water you mixed it with and your dose. See exactly how many units to draw on your syringe*.
Semaglutide · draw to
10units
- Volume
- 0.1 mL
- Strength
- 2.5 mg/mL
- Doses / vial
- 20
For information and record-keeping only, not medical advice. The calculator converts the numbers you enter and never recommends a peptide or a dose. Check every dose and unit with a licensed healthcare provider. Nothing you type leaves your browser.
How to use the peptide calculator.
Four inputs, one answer. Every result updates as you type, and Copy link saves your numbers in a link you can bookmark or share.
- 1
Pick your peptide
Tap one of the common picks or search all 63 peptides, blends and vitamins in the library. Not listed? Choose a custom peptide.
- 2
Enter the vial
For powder, choose the vial strength in mg and the bacteriostatic (BAC) water you added. For a pre-mixed vial, enter the strength printed on the label in mg/mL.
- 3
Enter your dose
Type the dose your provider gave you, in mg or mcg. Picking a peptide pre-fills a placeholder; replace it with your own number.
- 4
Read the syringe
Choose your syringe size. The calculator shows the units to draw on a U-100 insulin syringe, the volume in mL and the nearest printed mark.
The peptide math, in three lines.
Every peptide reconstitution calculator does the same three steps. Once you see them, you can check any result by hand. For a longer walk-through, read peptide math explained.
Concentration
vial strength (mg) ÷ liquid (mL)
gives mg/mL
Volume to draw
dose (mg) ÷ concentration
gives mL
Syringe units
volume (mL) × 100
gives units on U-100
Syringe units, explained.
Units on an insulin syringe measure volume, not the amount of peptide. On the common U-100 syringe, 100 units is 1 mL, so 1 unit is 0.01 mL. How much peptide a unit holds depends entirely on how the vial was mixed, which is why the units for the same dose change with the water.
mL to units on a U-100 syringe
| Volume | Units |
|---|---|
| 0.01 mL | 1 units |
| 0.02 mL | 2 units |
| 0.05 mL | 5 units |
| 0.1 mL | 10 units |
| 0.15 mL | 15 units |
| 0.2 mL | 20 units |
| 0.25 mL | 25 units |
| 0.3 mL | 30 units |
| 0.4 mL | 40 units |
| 0.5 mL | 50 units |
| 0.75 mL | 75 units |
| 1 mL | 100 units |
Syringe sizes and their scales
- 0.3 mL30 units
Marked every 1 unit · Finest scale; best for small draws
- 0.5 mL50 units
Marked every 1 unit · Small draws with more room
- 1 mL100 units
Marked every 2 units · The most common insulin syringe
- 3 mLNot in units
Marked every 0.1 ml · Standard syringe, read in mL
A dose rarely lands exactly on a mark. The calculator shows the exact units and the nearest mark on the barrel you chose; a smaller barrel rounds less.
Five common peptide calculation mistakes.
The calculator catches some of them for you. More in our guide to calculator mistakes.
- Mixing up mg and mcg
- 1 mg is 1,000 mcg. A dose typed in the wrong unit is off by a factor of a thousand, which is why the calculator flags any dose larger than the whole vial.
- Using the vial strength as the dose
- A 10 mg vial is the total powder in it, not the amount you take each time. The vial strength sets the concentration; your dose is a separate number.
- Forgetting the water changes the units
- The same dose takes more units when the vial is mixed with more water, because each unit holds less peptide. Recalculate whenever the water changes.
- Reading a U-40 or U-50 syringe as U-100
- Units are marks on the barrel, not a measure of the drug. This calculator assumes U-100 (100 units = 1 mL), the common type; check the label on your box.
- Reading a 3 mL syringe in units
- Insulin syringes stop at 1 mL. Bigger syringes are printed in mL, so for those the calculator gives the draw in mL instead of units.
The peptide calculator app that tracks every dose after.
Peppy is the peptide tracker app with this calculator built in. Enter the vial and the dose your provider gave you once, and it shows the units on your syringe each time you log a dose.
- The same units on your syringe, every time you log a dose
- A reminder when each dose is due
- Doses left in the vial, and when to reorder
- Injection sites that rotate
- A full dose history to show your provider
Free to start · no account
Every peptide in the calculator: 63 peptides, blends and vitamins.
The same library as the Peppy app, with the vial sizes and water volumes each one is commonly sold and mixed in. Use the calculator for any of them, or pick a custom peptide.
Metabolic
- Semaglutide
- Tirzepatide
- Retatrutide
- Cagrilintide
- Survodutide
- Liraglutide
- Dulaglutide
- Pramlintide
- Mazdutide
- SS-31
- MOTS-c
- AOD-9604
- Lipo-B12
- L-Carnitine
Growth
- Tesamorelin
- Sermorelin
- Ipamorelin
- CJC-1295
- CJC-1295 DAC
- GHRP-2
- GHRP-6
- Hexarelin
- IGF-1 LR3
- PEG-MGF
- Follistatin-344
Recovery
- BPC-157
- TB-500
- ARA-290
- Thymosin Beta-4
Longevity
- GHK-Cu
- Epitalon
- Pinealon
- Humanin
- FOXO4-DRI
- NAD+
Hormonal
- PT-141
- Melanotan II
- Melanotan I
- Gonadorelin
- Kisspeptin-10
- Testosterone Cypionate
- Testosterone Enanthate
Cognitive
- Semax
- Selank
- DSIP
- Cerebrolysin
Immune
- Thymosin Alpha-1
- KPV
- LL-37
- Thymalin
Antioxidant
- Glutathione
Vitamins
- Vitamin B12
- Vitamin B1
- Vitamin B3
- Vitamin B5
- Vitamin B6
- Vitamin B7
- Vitamin B9
Stacks
- Wolverine Stack
- Glow Stack
- KLOW Stack
- GH Stack
- Tessa Stack
Peptide calculator questions, answered.
Tracking a GLP-1? See the GLP-1 tracker. More answers in the help centre.
- What is a peptide calculator?
- A peptide calculator turns three numbers you already have into what to draw on your syringe: the amount of peptide in the vial, the liquid in the vial and the dose your provider gave you. It works out the concentration in mg per mL, the volume of that dose in mL, and that volume in units on a U-100 insulin syringe.
- How do I calculate peptide syringe units?
- Divide the vial strength by the water added to get the concentration (mg ÷ mL). Divide your dose by the concentration to get the volume in mL. Multiply the volume by 100 to get units on a U-100 syringe. For example, a 10 mg vial mixed with 2 mL is 5 mg/mL; a 1 mg dose is 0.2 mL, which is 20 units.
- How many units is 0.1 mL on an insulin syringe?
- On a U-100 insulin syringe, 0.1 mL is 10 units. Every 0.01 mL is 1 unit, so 0.25 mL is 25 units and 1 mL is 100 units.
- How much BAC water should I add to my peptide vial?
- Follow the instructions from your provider or pharmacy. The calculator offers the volumes commonly used for each vial so you can enter what you actually added. More water gives a weaker solution, so the same dose takes more units; less water does the opposite.
- Does the calculator tell me what dose to take?
- No. It only converts the numbers you enter. Picking a peptide pre-fills common values as placeholders to save typing; they are not recommendations. Always use the dose your licensed healthcare provider gave you and check every result with them.
- Which syringe size should I use?
- Use the syringe you have been given. A smaller barrel has a finer scale: 0.3 and 0.5 mL insulin syringes are marked every unit, a 1 mL every 2 units. If the draw is bigger than the barrel, the calculator says so and offers the size that holds it.
- Is there a peptide calculator app?
- Yes. Peppy is a peptide calculator app and peptide tracker for iPhone. It does the same maths as this page, then keeps your vial, reminds you when each dose is due, counts down how many doses are left and rotates your injection sites. It is free to start, with no account.
- Is this peptide calculator free?
- Yes. The calculator on this page is free, needs no sign-up and runs entirely in your browser; nothing you type is sent anywhere. Copy the link to share or save a calculation.
Keep the math. Track the doses.
Download Peppy, the peptide calculator app and peptide tracker for iPhone. Free to start, no account.