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Free research tool · 26 compounds · Works offline as an app

Peptide Reconstitution Calculator

Vial size, bacteriostatic water and the amount you want to measure in — concentration and exact U-100 syringe units out. Now with a live dose chart for your setup, syringe-size guidance, and the vial size to buy. A laboratory measurement tool, not dosing guidance.

Want it on your phone? The same calculator lives at Vial Tool as an installable app — add it to your home screen and it works with no signal. Compound-specific printable charts: tirzepatide · semaglutide · retatrutide · GHK-Cu · BPC-157 · which syringe to use.
What this tool is. Reconstitution is the lab step of dissolving a lyophilized (freeze-dried) research peptide in bacteriostatic water so it can be measured accurately. This calculator does that measurement math only — concentration and the volume/units that correspond to a target amount. It is not a dosing protocol, not medical advice, and not a suggestion to administer anything. All referenced compounds are for laboratory and research use only — not for human consumption.

How the math works

Every result comes from three simple steps — no magic:

Step 1 — Concentration

Divide the peptide in the vial by the water you added.
concentration (mg/mL) = vial mg ÷ water mL
Example: 5 mg ÷ 2 mL = 2.5 mg/mL (2,500 mcg/mL).

Step 2 — Volume for your target amount

Divide the amount you want by the concentration.
volume (mL) = target mcg ÷ concentration (mcg/mL)
Example: 250 mcg ÷ 2,500 mcg/mL = 0.10 mL.

Step 3 — Syringe units

On a U-100 insulin syringe, 1 unit = 0.01 mL, so multiply volume by 100.
units = volume (mL) × 100
Example: 0.10 mL × 100 = 10 units.

Common questions
What is bacteriostatic water?

Bacteriostatic water is sterile water with 0.9% benzyl alcohol added to inhibit bacterial growth, which is why it's the standard diluent for reconstituting research peptides in a lab setting. The amount you add sets your concentration — more water means a lower concentration per unit.

Why insulin units instead of mL?

Research peptide volumes are tiny — often a fraction of a milliliter — so U-100 insulin syringes (marked in units, where 100 units = 1 mL) give far more precise, readable measurements than a standard mL syringe.

Is this a dosing recommendation?

No. This is a measurement/dilution calculator only. It converts numbers you enter into a concentration and a corresponding volume. It does not recommend an amount, and nothing on this site is medical advice. All compounds referenced are strictly for laboratory and research use — not for human consumption.

Where do I buy tested research peptides?

See our independent, COA-focused vendor rankings — we score every research-peptide company on purity, third-party Certificates of Analysis, reputation, and shipping.

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