Peptide Dosage Calculator
Calculate exact injection volumes, BAC water ratios, and total doses for any peptide or peptide blend. Free, instant, no login needed. Works for semaglutide, tirzepatide, BPC-157, TB-500, CJC-1295, ipamorelin, and 20+ other peptides, plus custom multi-peptide blends.
How reconstitution math works
Your vial contains a fixed amount of peptide, measured in milligrams. The bacteriostatic water you add sets the concentration:
- Concentration = vial contents (mg) ÷ BAC water added (ml)
- Injection volume = desired dose ÷ concentration
- Syringe units = injection volume (ml) × 100, on a standard U-100 insulin syringe
Worked example: a 5 mg vial reconstituted with 2 ml of BAC water gives 2.5 mg/ml (2,500 mcg/ml). A 250 mcg dose is 250 ÷ 2,500 = 0.1 ml — which is 10 units on a U-100 insulin syringe.
The calculator does this math for you in both directions: enter any two of vial size, water volume, and target dose, and it solves for the draw. It also handles mcg/mg unit conversion and multi-peptide blend ratios.
What it supports
- Single-peptide reconstitution (mg or mcg dosing)
- Peptide blend mode for multi-compound vials (e.g. BPC-157 + TB-500 + GHK-Cu + KPV)
- U-100 insulin syringe unit conversion
- Saved calculations — create a free account to store your setups and log doses against your protocol
*The calculator presents math, not dosing guidance. Peptides referenced are for research purposes only. Always verify calculations and consult a licensed healthcare provider.*
Frequently asked questions
What does this calculator do?
This calculator determines your injection volume. Enter your vial size, the amount of bacteriostatic water you used to reconstitute, and your desired dose — it tells you exactly how many units to draw on your insulin syringe. For research purposes only. Always verify with your healthcare provider.
What is bacteriostatic water?
Bacteriostatic water (BAC water) is sterile water containing 0.9% benzyl alcohol used to reconstitute lyophilized peptide powder. The volume you add determines the concentration of your solution.
How do I read the syringe result?
The result shows units corresponding to tick marks on a U-100 insulin syringe. Draw up to that mark. Always double-check before use and consult your healthcare provider.
Can I use this for peptide blends?
Yes — switch to "Peptide Blend" mode to calculate volumes for multi-peptide combinations like KLOW (BPC-157, TB-500, GHK-Cu, KPV).
Can I save my calculations?
Yes — use "Load Saved Calculation" to store and reload common calculations. Create a free account to also log and track doses over time.
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