Semaglutide calculator

Semaglutide Reconstitution Calculator

Semaglutide comes as a freeze-dried powder you mix with bacteriostatic water. Put in your vial size and water amount and the calculator gives you the exact units to draw on a U-100 insulin syringe. For information only, not dosing advice.
Syringe type

Draw to

10units
010203040506070809010010u

On a U-100 insulin syringe. 100 units = 1 mL.

Concentration
2.5 mg/mL
Per dose
0.1 mL
Doses / vial
20

Common Semaglutide vial sizes

Semaglutide is commonly supplied as 2, 3, 5, 10 mg vials. A common starting point is 5 mg reconstituted with 2 mL of bacteriostatic water, which gives 2.5 mg/mL.

How to reconstitute Semaglutide

  1. Add 2 mL of bacteriostatic water (or your chosen volume) slowly down the side of the vial.
  2. Swirl gently until the solution is clear. Do not shake.
  3. Enter your vial size, water volume, and dose in the calculator above.
  4. Draw to the exact unit mark it highlights on the syringe.

Example dose in units

At 2.5 mg/mL, a 0.25 mg dose of Semaglutide is about 10 units on a U-100 insulin syringe. Change any value above to match your own vial.

Storage and handling

Semaglutide has an approximate half-life of 168 hours. Once reconstituted, peptides are generally kept refrigerated and protected from light, and are often used within about 28 days. See our storage guide for general handling information.

Frequently asked questions

How much bacteriostatic water do I add to semaglutide?
Any volume works mathematically; more water means an easier-to-measure draw. The calculator shows the resulting units for whatever volume you choose, and the recommended-water option finds a clean number.
How many units is a 0.25 mg semaglutide dose?
At 2.5 mg/mL (5 mg in 2 mL), 0.25 mg is 0.1 mL, which is 10 units on a U-100 syringe. Enter your own vial and water above to confirm.

Related calculators and guides

Keep this calculation in your pocket

Stackr saves every vial you reconstitute, tracks doses remaining, and reminds you to reorder before you run out. The reference app for people who take their protocol seriously.

Educational tool only, not medical advice. Peptides are research chemicals, not for human consumption. Full disclaimer.