Peptide Reconstitution Calculator
Peptide Reconstitution Calculator
You bought a peptide. Now what? Pick your compound, confirm the mg printed on your vial, and we'll tell you the recommended amount of bacteriostatic water to add — plus a step-by-step walkthrough for mixing it safely.
Two Steps. Then You're Ready to Mix.
Pick your peptide, confirm the vial strength printed on the label, and we'll recommend the optimal bacteriostatic water amount to add. The vial strength stays constant — we adjust the water to produce a clean, easy-to-dose concentration.
The most common mistake in peptide reconstitution is treating it as guesswork. It isn't. Each peptide has a practical sweet spot for bacteriostatic water volume — enough to keep injection sizes comfortable, but not so much that small doses become impossible to measure accurately. The recommendations on this page reflect common practitioner conventions, calibrated so that your downstream dosing math stays clean and predictable.
This calculator is designed to pair with the Peptide Dosing Calculator. Once you've reconstituted your vial here, jump there to figure out exactly how much to draw on your insulin syringe for your prescribed dose.
How to Reconstitute Your Vial
An 8-step walkthrough customized to your selected peptide and vial strength. Always work in a clean area with sterile supplies.
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1
Gather your supplies. You'll need: the lyophilized peptide vial, a vial of bacteriostatic water, a reconstitution syringe (typically a 3 mL syringe with a long needle), alcohol swabs, and a clean flat workspace. Wash your hands thoroughly.
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2
Wipe both vial tops. Use a fresh alcohol swab on the rubber stopper of both the peptide vial and the bacteriostatic water vial. Allow a few seconds to air dry — do not blow on it.
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3
Draw 3 mL of bacteriostatic water. Pull the plunger back to the 3 mL mark on your reconstitution syringe (or to 300 units if using a U-100 insulin syringe). Insert the needle into the bac water vial, invert the vial, and slowly draw the exact amount.
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4
Inject water down the side of the peptide vial. This is the part most people get wrong. Tilt the peptide vial slightly and let the water run gently down the inside of the glass — do not blast it directly onto the lyophilized powder. This protects the peptide's molecular structure during reconstitution.
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5
Swirl gently — do not shake. Roll the vial between your palms or swirl in a slow circle until the powder fully dissolves. Most peptides clear within 30 to 60 seconds. Never shake the vial — agitation creates foam and can denature the peptide.
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6
Inspect the solution. It should appear clear and colorless. If you see cloudiness, particulate matter, or unexpected discoloration, do not use the vial.
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7
Label and store. Write the reconstitution date on the vial label or cap. Refrigerate at 36–46°F (2–8°C) and use within 28 days.
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8
You're ready to dose. Use a fresh insulin syringe for each injection. To calculate exactly how much to draw for your prescribed dose, visit the Peptide Dosing Calculator →
Your vial is reconstituted. Next up: figure out exactly how much to draw on your insulin syringe for your prescribed dose. The Peptide Dosing Calculator handles the math for you.
Open Dosing Calculator →