Peptide Reconstitution Calculator

Pick your peptide to load its reference dose range, enter your vial size and how much bacteriostatic water you're adding, and get the exact number of units to draw on a U-100 insulin syringe — plus concentration and doses per vial.

DRAW ON INSULIN SYRINGE (U-100)
10.0 units
= 0.100 mL
2500mcg/mL
CONCENTRATION
20
DOSES PER VIAL

PEPTIDE REFERENCE

Select a peptide from the dropdown to see its commonly cited dose range, frequency, route, and typical cycle length — and to auto-fill the calculator.

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How to use this calculator

Choose your peptide from the dropdown and the reference dose range loads automatically — you can quick-fill the low, standard, or high dose with one tap, or type your own. Then enter your vial size in mg and the amount of bacteriostatic water you're adding. The calculator instantly gives you the units to draw.

How the math works

A U-100 insulin syringe has 100 units per mL. Once you know your concentration (total mcg ÷ total mL), the units to draw is simply dose ÷ concentration × 100.

Worked example: a 5mg vial reconstituted with 2mL of bacteriostatic water gives 2500 mcg/mL. A 250mcg dose is 250 ÷ 2500 = 0.1 mL = 10 units.

Why the water amount doesn't change your dose

This is the part that confuses almost everyone. The amount of bacteriostatic water you add doesn't change how much peptide is in the vial — it only changes the concentration, and therefore how many units you draw for the same dose. Add more water and you draw more units; add less and you draw fewer. Either way you get the same dose and the same number of doses per vial. Pick whatever volume puts your dose in an easy-to-read range.

How to reconstitute a peptide

Reconstitution means adding bacteriostatic water to a lyophilized (freeze-dried) peptide vial so it can be injected. Let the vial reach room temperature, swab both stoppers with alcohol, and add the water slowly down the side of the vial rather than blasting it onto the powder. Swirl gently — never shake, since peptides are fragile protein chains. Store reconstituted vials refrigerated and use them within roughly 2–4 weeks. For a full walkthrough, see our reconstitution guide.

Frequently asked questions

How do you calculate peptide reconstitution?

Units to draw = (dose in mcg ÷ total mcg in vial) × (mL of water × 100). For example, a 5mg vial (5000mcg) reconstituted with 2mL of bacteriostatic water, dosing 250mcg: 250 ÷ 5000 × 200 = 10 units on a U-100 insulin syringe.

How much bacteriostatic water should I add?

There's no single correct amount. The water volume doesn't change how much peptide you have — only the concentration, and therefore how many units you draw. Pick a volume that puts your dose in an easy-to-read range, roughly 10–50 units on a U-100 syringe.

What is the recommended dose for BPC-157?

Commonly cited ranges are 250mcg (low), 500mcg (standard), and 1000mcg (high), dosed once or twice daily. This calculator includes reference dose ranges for 45 peptides.

How many units is 250mcg of BPC-157?

It depends on your dilution. With a 5mg vial and 2mL of bacteriostatic water, 250mcg = 10 units on a U-100 insulin syringe. With 5mL of water, the same 250mcg dose = 25 units.

What is a U-100 insulin syringe?

A U-100 insulin syringe has 100 units per 1 mL. This is the standard syringe used for subcutaneous peptide injections, and it's what this calculator's unit output is based on.

Does more water make the peptide dose weaker?

No. This is the most common misconception. Adding more bacteriostatic water means you draw more units for the same dose. The total peptide in the vial and the number of doses stay exactly the same.

For educational and research purposes only. Not medical advice. Dose ranges shown are reference figures commonly cited in research contexts, not prescriptions — always verify your own math and consult a physician before starting any peptide protocol. BioHack is a tracking tool and does not sell peptides.