RedoseThe free peptide calculator
Reconstitution, dose-to-units, BAC water, and half-life, all in one place. Enter your vial size and water and get the exact units to draw on a U-100 insulin syringe. No signup, no math.
How much bacteriostatic water is already in the vial? Enter your numbers to get the exact units to draw on a U-100 insulin syringe.
How the peptide reconstitution math works
Every peptide dose comes down to three numbers: how much peptide is in the vial, how much water you add, and the dose you want. From those, the rest is arithmetic.
Concentration
vial mg ÷ water mL
5 mg ÷ 2 mL = 2.5 mg/mL
Volume to draw
dose mg ÷ concentration
0.25 mg ÷ 2.5 = 0.1 mL
Units
volume mL × 100
0.1 mL × 100 = 10 units
Calculator FAQ
How do you calculate a peptide dose?
First find the concentration by dividing the vial amount (mg) by the bacteriostatic water you added (mL). Then divide your target dose (in mg) by that concentration to get the volume to draw, and multiply by 100 to read it as units on a U-100 insulin syringe.
How many units should I draw?
On a standard U-100 insulin syringe, 100 units equals 1 mL. So units to draw = (dose in mg ÷ concentration in mg/mL) × 100. The reconstitution tab does this for you automatically.
What is bacteriostatic water?
Bacteriostatic water is sterile water with 0.9% benzyl alcohol that inhibits bacterial growth, which is why it's commonly used to reconstitute multi-dose peptide vials. The amount you add sets your concentration.
Is the peptide calculator free?
Yes, every calculator here is free and works in your browser with no signup. For one-tap logging, auto site rotation, and live vial inventory, the Redose app carries these calculators on iPhone and Android.