Peptide reconstitution calculator
Enter your vial, the bac water you add and your prescribed dose to get the exact units to draw on a U-100 syringe, with every step shown.
Your numbers
Syringe
1 mL · 2-unit marks
Work backwards
Find the water for a given reading in units.
Draw to 50 units, 0.5 mL.
Draw to
50units
0.5 mL
- Strength
- 5 mg/mL
- Each unit holds
- 50 mcg
- Doses per vial
- 4
- whole doses
Show the math
Strength once mixed
10 mg ÷ 2 mL equals 5 mg/mL
Amount in each unit
5 mg/mL × 1,000 ÷ 100 equals 50 mcg
On a U-100 syringe, 1 unit is 0.01 mL, and 1 mg is 1,000 mcg.
Volume to draw
2.5 mg ÷ 5 mg/mL equals 0.5 mL
In syringe units
0.5 mL × 100 equals 50 units
Doses in the vial
10 mg ÷ 2.5 mg equals 4
Some liquid always stays in the vial and needle, so you may get fewer.
This is arithmetic, not medical advice. Confirm with your prescriber or pharmacist.
How our calculator worksAdvanced
Vial capacityOptional
The volume printed on the vial or its box, not the mg. We’ll tell you if the water won’t fit.
How to use this calculator
Enter the vial amount
Type the mg printed on the vial label: the amount of powder inside, not the size of the vial.
Enter the water you add
Type the mL of bacteriostatic water your pharmacy’s instructions specify. This sets the concentration.
Enter your prescribed dose
Type the dose your prescriber gave you, and pick mg or mcg to match how it is written.
Pick your syringe and read the result
Choose 30, 50 or 100 units to match your syringe. The result shows the units and mL to draw, and the line on the syringe.
How the peptide calculator works
Every result comes from two lines of arithmetic. First the strength of the mixed vial, then the volume that holds your dose:
mg/mL = vial mg ÷ water mL
units = dose mg ÷ mg/mL × 100
On a U-100 insulin syringe, 100 units is 1 mL. So a 10 mg vial with 2 mL of water is 5 mg/mL, and a 2.5 mg dose is 0.5 mL, or 50 units (numbers for illustration only, not a dose).
Some people call this a peptide dosage calculator. It doesn’t choose a dose: it converts the one you were prescribed into syringe units. The full method, rounding rules and warnings are on how our calculator works.
Concentration: mg per mL
The water you add doesn’t change how much peptide is in the vial; it changes how concentrated the liquid is. Twice the water means half the mg in each mL, so the same dose takes twice as many units.
Bigger unit numbers are easier to measure but mean more liquid per injection. The volume itself comes from your pharmacy’s instructions. To see how a volume relates to the units each dose reads, switch on Work backwards, or use the bac water calculator.
Doses per vial
Divide the vial amount by your dose: a 10 mg vial and a 2.5 mg dose give 4 doses. We show whole doses, plus the exact figure when there’s a part dose left. A little liquid always stays in the vial and needle, so you may get slightly fewer.
Which syringe size to use
30 and 50-unit syringes have a mark for every unit; 100-unit syringes mark every 2 units. A smaller syringe makes the same draw easier to read, but it has to hold the whole draw: anything over 30 units won’t fit a 30-unit syringe. Use the syringe your pharmacy supplied, and see how to read an insulin syringe.
Questions people ask
Can I use the peptide calculator in mcg?
Yes. Switch the dose to mcg and type it as written on your prescription; the answer is the same either way, because 1 mg is 1,000 mcg. A 250 mcg dose is 0.25 mg. The vial amount stays in mg, since that is how vials are labeled.
Does adding more water change how much peptide I get?
No. The water changes the concentration, not the amount in the vial. More water means each mL holds less, so the same dose takes more units on the syringe. A 10 mg vial still holds 10 mg whether you add 1 mL (10 mg/mL) or 2 mL (5 mg/mL). Use the volume your pharmacy’s instructions give.
What if the units fall between two marks on my syringe?
The calculator shows the exact units and the nearest printed mark on the syringe you picked: whole units on 30 and 50-unit syringes, every 2 units on a 100-unit syringe. If drawing to that mark changes the amount by more than 5%, you’ll see a caution with the exact difference. Ask your pharmacist how to measure it.
Can I use this peptide calculator for blends?
For a vial with more than one compound, use the peptide blend calculator. It splits the draw into each compound’s share, because every compound in a blend dissolves in the same water and has its own concentration. Enter each compound’s mg exactly as printed on the label.
Can Peptinote tell me how many units to take?
No. Peptinote never suggests a dose. Enter the dose your prescriber gave you, and the calculator shows how to measure it: the units, the mL and where the line sits on your syringe, with every step of the math. If you aren’t sure what your dose is, ask your prescriber or pharmacist before drawing anything. How our calculator works.
Vial calculators
Pre-filled with the vial size. You add the water and the dose your prescriber gave you.
Related
Calculators
Guides
Every result is plain arithmetic from formulas we publish in full and check with automated tests. Peptinote doesn’t suggest doses and never sells or links to sellers of peptides.