Vial strength + BAC water volume + desired dose → exact units on a U-100 insulin syringe. Math runs locally - nothing leaves your browser.
Start from a peptide
Pick a common peptide to autofill typical vial size, BAC water, and starting dose. Every value below stays editable.
CustomEnter your own vial, BAC, and dose values - or pick a peptide above.
Inputs
Result
- units
Concentration - mg / ml
Volume / dose - ml
Doses / vial -
Vial lasts - days @ weekly
How peptide reconstitution math works
Reconstitution is the process of dissolving a lyophilised (freeze-dried) peptide in bacteriostatic water so it can be drawn into an insulin syringe. The math is deterministic:
Concentration (mg/ml) = vial peptide mass (mg) ÷ BAC water added (ml).
U-100 syringe units = volume per dose (ml) × 100. (U-100 syringes mark 1 ml = 100 units, so 0.01 ml = 1 unit.)
Doses per vial = vial peptide mass (mg) ÷ desired dose (mg).
Worked example - semaglutide 5 mg vial, 2 ml BAC water, 0.25 mg dose:
Concentration = 5 ÷ 2 = 2.5 mg/ml
Volume per dose = 0.25 ÷ 2.5 = 0.10 ml
U-100 units = 0.10 × 100 = 10 units
Doses per vial = 5 ÷ 0.25 = 20 doses (≈ 20 weeks at weekly dosing)
For research use only. Not for human consumption.
The calculator performs deterministic math from your inputs - it does
not recommend doses. Confirm reconstitution figures against the
vial / BAC water label before drawing.