The free peptide reconstitution and dosage calculator. Enter your vial size and bacteriostatic water, and get concentration, units to draw, and draws per vial instantly. Works for any peptide — retatrutide, tirzepatide, semaglutide, BPC-157 and more. Research use only.
Inputs
mg
ml
mcg
Vial:
Water:
Units assume a U-100 syringe (100 units = 1 ml). This is research math only, not dosing or medical advice.
Results
Units to draw-
Liquid volume per draw-
Concentration-
Per unit-
Draws per vial-
Round physical measurements carefully and follow your lab protocol.
Get it on your phone
PepSync — the peptide calculator app
Prefer to run the numbers on your phone at the bench? PepSync is our peptide calculator app: the same reconstitution and dosage math, plus saved vials and quick presets, offline. Free on the App Store.
Sometimes called a peptide dosing calculator or peptide dosing chart — it's the same reconstitution math: it turns your vial and bacteriostatic water into a concentration and a units-per-draw reference. It reads out the reconstitution solution concentration in mg/ml and mcg per unit. Research figures only, never a dose recommendation.
How the math works
1
Concentration = mg ÷ ml. Peptide milligrams in the vial divided by the millilitres of bacteriostatic water you add. 10 mg in 2 ml = 5 mg/ml.
2
Per unit. On a U-100 syringe, 1 unit = 0.01 ml. So mcg per unit = concentration × 10. At 5 mg/ml that's 50 mcg per unit.
3
Units to draw = target ÷ mcg per unit. To pull 250 mcg at 50 mcg/unit, you draw 5 units.
This tool performs arithmetic for laboratory research only. It makes no recommendation about human or veterinary use. If your goal is treating something in yourself, that's a job for a licensed clinician, not a calculator.
Frequently asked
How does the reconstitution calculation work?
Concentration = peptide mg ÷ bacteriostatic water ml. On a U-100 syringe, 100 units = 1 ml, so 1 unit = 0.01 ml. The calculator turns that into mcg per unit and units to draw. Research math only.
How much bacteriostatic water should I add?
There's no single right answer — the water volume sets the concentration. Most researchers add 1–3 ml per vial to keep draw volumes small. See our bacteriostatic water guide for details.
Is this dosing advice?
No. It's a research-use concentration tool that does arithmetic only, with no recommendation about human or veterinary use.