Peptide Watchdogs
Free research tool · PepSync

Peptide calculator

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.

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PepSync — the peptide calculator app

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Get PepSync → Coming to iPhone after App Store approval

Per-peptide calculators

Presets for the most-searched compounds — vial size and water pre-filled, ready to adjust.

Retatrutide Calculator Tirzepatide Calculator Semaglutide Calculator BPC-157 Calculator TB-500 Calculator BPC-157 + TB-500 blend Calculator CJC-1295 + Ipamorelin Calculator Tesamorelin Calculator Sermorelin Calculator PT-141 Calculator GHK-Cu Calculator Ipamorelin Calculator Glutathione Calculator NAD+ Calculator AOD-9604 Calculator Melanotan 2 Calculator IGF-1 LR3 Calculator MOTS-c Calculator KPV Calculator Semax Calculator Selank Calculator CJC-1295 Calculator Epithalon Calculator Cagrilintide Calculator Hexarelin Calculator HGH Fragment 176-191 Calculator Thymosin Alpha-1 Calculator SS-31 Calculator Survodutide Calculator Mazdutide Calculator GLOW blend Calculator KLOW blend Calculator

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.

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