Peptide calculator: reconstitution, dose and syringe units
This free peptide calculator turns a vial strength, the liquid added and a dose into a concentration, a volume and syringe units. To find how many units to draw, divide the vial strength by the liquid added to get the concentration, divide your dose by the concentration to get the volume in mL, then multiply by 100 for units on a U-100 syringe. Enter your own numbers below and the calculator does it for you.
The formula
- Concentration
- vial strength (mg) ÷ liquid added (mL) = mg per mL
- Volume to draw
- dose (mg) ÷ concentration (mg/mL) = mL
- Syringe units
- volume (mL) × 100 = units on a U-100 syringe
- Doses per vial
- vial strength ÷ dose
Worked example
- A 5 mg vial reconstituted with 2 mL of liquid has a concentration of 5 ÷ 2 = 2.5 mg/mL, which is 2,500 mcg/mL.
- A 250 mcg dose is 0.25 mg. 0.25 ÷ 2.5 = 0.1 mL.
- 0.1 mL × 100 = 10 units on a U-100 syringe.
- The vial holds 5 mg ÷ 0.25 mg = 20 doses of that size.
Peptide reconstitution chart
| Liquid added | Concentration | 100 mcg | 250 mcg | 500 mcg |
|---|---|---|---|---|
| 1 mL | 5 mg/mL | 2 units | 5 units | 10 units |
| 2 mL | 2.5 mg/mL | 4 units | 10 units | 20 units |
| 3 mL | 1.67 mg/mL | 6 units | 15 units | 30 units |
| 5 mL | 1 mg/mL | 10 units | 25 units | 50 units |
Charts by vial size
Common questions
Is this peptide calculator free?
Yes. It is free, runs in your browser, needs no sign-up and does not send the numbers you enter anywhere.
Can I enter the dose in mg instead of mcg?
Yes. Switch the dose unit between mcg and mg. The calculator shows the result in mL and in units on a U-100 syringe.
How do I calculate peptide reconstitution?
Divide the amount of peptide in the vial by the volume of liquid you add. A 10 mg vial with 2 mL added is 5 mg/mL. Divide your dose by that concentration for the volume to draw.
Does adding more water change the dose?
It changes the concentration, not the amount of peptide in the vial. More liquid means a weaker solution, so the same dose takes up more volume and more units on the syringe.
How many units is 250 mcg?
It depends on the concentration. At 2.5 mg/mL (a 5 mg vial with 2 mL added) 250 mcg is 10 units on a U-100 syringe. At 5 mg/mL it is 5 units.
What does U-100 mean?
U-100 means the syringe is graduated at 100 units per mL, so each unit mark is 0.01 mL.
Does this calculator tell me what dose to take?
No. It converts numbers you supply. The dose itself must come from your prescriber or pharmacist.
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Keep the numbers with your log
Record each vial's strength and status in PepVault, next to every dose you log. Free for Android, iPhone, iPad and Mac.
For Android, iPhone, iPad and Mac. On the App Store the app is listed as PeptideMate.