Mixing & syringe converter

Divide the mg in the vial by the mL of water you added: that is the concentration in mg per mL. Divide your prescribed dose by that concentration to get mL, then multiply by 100 for units. Example: 10 mg with 2 mL of water is 5 mg/mL, so 2.5 mg is 0.5 mL, which is 50 units.

No. You enter the dose written on your prescription or pharmacy label, and the tool only converts it between mg, mL and syringe units. Your prescriber decides the dose.

The most common insulin-style syringe in the US. U-100 means 100 units fill 1 mL, so 1 unit is 0.01 mL. They come in 0.3 mL (30 units), 0.5 mL (50 units) and 1 mL (100 units) sizes.

Most calculators ask how much water you added and give you an awkward reading like 17.3 units. Planning backwards lets your dose land on a clean mark of the syringe, which is easier to read. The tool still warns you when the water would not fit in the vial or is too little to measure.

The same formulas run in the Embera app, where they are checked against 24 worked examples every time the app is built. This page runs the same 24 checks.