Peptide Reconstitution Calculator
Vial size + bacteriostatic water + dose → exact units on an insulin syringe. Free, instant, with typical values pre-loaded for 30+ peptides.
Peptide reference library
Typical vial sizes, water amounts, reported dose ranges and storage for every major peptide.
Healing & Recovery
Growth Hormone
Longevity & Cellular
Skin, Tanning & Sexual Health
Immune Support
Popular comparisons & stacks
Head-to-head verdicts and the combination protocols people actually run.
How the math works
1. Concentration. A 5 mg vial mixed with 2 ml of bacteriostatic water gives 5,000 mcg ÷ 2 ml = 2,500 mcg/ml.
2. Dose volume. For a 250 mcg dose: 250 ÷ 2,500 = 0.1 ml.
3. Syringe units. On a U-100 insulin syringe, 1 ml = 100 units, so 0.1 ml = 10 units. That's the number you draw to.
The calculator above does exactly this — nothing more. The math is deterministic; the reason to use a calculator is avoiding the decimal-place errors that are easy to make at 2am with a 30-unit syringe in hand.
Frequently asked questions
How does peptide reconstitution math work?+
Divide the peptide amount (in mcg) by the water volume (in ml) to get concentration. Your dose in ml = desired mcg ÷ concentration. On a U-100 insulin syringe, 1 ml = 100 units, so multiply ml by 100 to get units to draw.
How much bacteriostatic water should I add?+
There is no single right amount — water changes only the concentration, not the peptide. More water = more volume per dose (easier to measure small doses); less water = smaller injections. Most 5 mg vials are mixed with 2–3 ml. Each peptide page on this site lists the commonly used amount.
What syringe do these 'units' refer to?+
A standard U-100 insulin syringe, where 100 units equal 1 ml. If your syringe is 0.5 ml (50 units) or 0.3 ml (30 units), the unit markings still match — a dose of 10 units is the same volume on any U-100 syringe.
Bacteriostatic water vs sterile water — which one?+
Bacteriostatic water contains 0.9% benzyl alcohol, which prevents bacterial growth and allows multi-week use of a reconstituted vial. Plain sterile water has no preservative and is only appropriate for single immediate use.
New to this? Start with the step-by-step reconstitution guide.