Common vial sizes and water amounts
| Vial | Water | What that gives you |
|---|---|---|
| 2 mg | 1 mL | 2 mg/mL; 0.25 mg = 12.5U |
| 5 mg | 2 mL | 2.5 mg/mL; 0.25 mg = 10U |
| 5 mg | 2.5 mL | 2 mg/mL; 0.5 mg = 25U |
| 10 mg | 4 mL | 2.5 mg/mL; 1 mg = 40U |
Worked examples
Concentration 2.5 mg/mL → 25 mcg per unit → draw 10 units (0.1 mL) on a 30U syringe. That vial holds about 20 such draws.
Concentration 2 mg/mL → 20 mcg per unit → draw 12.5 units (0.125 mL) on a 30U syringe. That vial holds about 8 such draws.
Concentration 2.5 mg/mL → 25 mcg per unit → draw 40 units (0.4 mL) on a 50U syringe. That vial holds about 10 such draws.
Notes for this calculator
Aim for a concentration around 2 to 2.5 mg/mL: a 0.25 mg entry lands at 10 to 12.5 units, which is easy to read on a 30U syringe, and a 1 mg entry still fits a 50U. Mixing a 5 mg vial with only 1 mL puts 0.25 mg at 5 units, where a half-unit error is 10% of the draw.
Add the vial price on the left and the card shows cost per draw. For semaglutide that number is usually the one people are actually deciding on.
Vials for this calculator: see what ThePeptideStore carries. Supplies around the vial are in the kit above.
Common questions
How many units is 0.25 mg of semaglutide?
At 2.5 mg/mL (5 mg in 2 mL) it is 10 units. At 2 mg/mL it is 12.5 units. At 5 mg/mL (5 mg in 1 mL) it is only 5 units, which is hard to measure.
How much bacteriostatic water for a 5 mg semaglutide vial?
2 mL gives 2.5 mg/mL and puts a 0.25 mg entry at 10 units. 2.5 mL gives 2 mg/mL. Both keep the draw readable.
How many draws are in a 5 mg vial?
5 mg at 0.25 mg per entry is 20 draws; at 0.5 mg it is 10. The calculator shows doses per vial and cost per draw.
Does the calculator recommend a dose?
No. You enter the dose your protocol calls for and it converts that into syringe units, mL, and doses per vial. It never suggests what to take.
Why is my draw too big for the syringe?
The concentration is low for that dose. Either use a larger U-100 syringe or mix the next vial with less water. The calculator shows the exact water amount that would fit your syringe.