Reconstitution calculator

Enter how many milligrams are in your vial and how much bacteriostatic water you're adding. You'll get the concentration straight away, plus the mark to draw to on a standard 100-unit insulin syringe. It's just arithmetic on your own numbers — nothing is recommended.

5 mg/ml5,000 mcg per ml
50 mcgper 1 unit
500 mcgper 10 units
200units in the vial
5 units0.05 ml on a 100-unit syringe

Pure arithmetic on the numbers you type — nothing is recommended, stored, or sent anywhere. Always follow the instructions supplied with your own vial.

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How reconstitution maths works

Two numbers decide everything: how much peptide is in the vial, and how much water you add.

Does more water make it weaker?

Not weaker overall — the vial still holds the same total peptide. More water just spreads it across more volume, so each unit on the syringe carries less. Many people add a bit more water on purpose because larger marks are easier to read and measure accurately. Less water means fewer units for the same amount, which can be fiddly.

A note on accuracy

The maths is exact, but the real world isn't: a little liquid always clings to the vial and needle, and syringe markings have their own tolerance. This tool shows the ideal figures for the numbers you enter — it doesn't tell you what to take, and it isn't a substitute for the instructions that came with your product.

Do it once, then let the app remember

Peptide Wizard stores each vial you reconstitute — the mg, the water, the concentration and the date you mixed it — so the units are always there when you need them and you're never redoing the sum. It also tracks cost per dose, warns you before a mixed vial expires, and reminds you when a dose is due.