Semaglutide reconstitution calculator
Enter your Semaglutide vial size and the bacteriostatic water you are adding. The calculator shows the resulting concentration and marks the exact units on a U-100 or U-40 syringe.
Compounded semaglutide usually arrives as a lyophilised powder that has to be mixed before use. Enter the vial strength and the water you are adding to see the concentration and the units on the syringe.
Verify every dose with your prescriber or pharmacist.
This is an educational arithmetic tool. It does not know your prescription or your product, it does not recommend a dose, and it is not medical advice.
How to reconstitute Semaglutide
Reconstitution is arithmetic, not chemistry. The milligrams in the vial divided by the millilitres of bacteriostatic water gives the concentration in mg/mL. Your dose divided by that concentration gives the injection volume, and that volume multiplied by your syringe's units-per-mL gives the units to draw. More water means a lower concentration and more units for the same dose, which is easier to measure accurately.
FDA prescribing information for Ozempic/Wegovy: terminal half-life ≈ 1 week (~165 h); Tmax 1–3 days after subcutaneous dosing.
Semaglutide calculator FAQ
- How much bacteriostatic water should I add to a Semaglutide vial?
- There is no single correct amount. More water makes small doses easier to measure; less water keeps the injection volume down. The right choice depends on your prescription and product, so decide it with your prescriber or pharmacist — this calculator only shows the maths for the numbers you enter.
- Does adding more water change the dose?
- No. The amount of Semaglutide in the vial is fixed. Extra water spreads the same milligrams across more volume, so you draw more units for the same dose.
Try the general reconstitution calculator or browse all free tools.