Semaglutide dosage calculator
Convert the semaglutide dose you were prescribed, in milligrams, into units on your syringe, for any vial strength. From a licensed medical weight loss clinic in Mission Viejo.
Medically reviewed by Dr. Nezar Dahdal, Medical Director · last reviewed September 2026
Semaglutide dose calculator
Enter the dose your prescriber gave you and the concentration printed on your vial label. The calculator converts it to units on a U-100 insulin syringe.
Enter your prescribed dose and your vial concentration to see the units.
This converts a dose you have already been prescribed. It does not recommend a dose. Always use the concentration printed on your pharmacy label. If the number here does not match what you were told, stop and call your prescriber before injecting.
Semaglutide units chart by vial strength
The calculator's conversions for every standard dose step and the vial strengths pharmacies most often dispense. Find your prescribed dose, then your vial concentration.
| Prescribed dose | 1 mg/mL vial | 2.5 mg/mL vial | 5 mg/mL vial |
|---|---|---|---|
| 0.25 mg | 25 units (0.25 mL) | 10 units (0.1 mL) | 5 units (0.05 mL) |
| 0.5 mg | 50 units (0.5 mL) | 20 units (0.2 mL) | 10 units (0.1 mL) |
| 1 mg | 100 units (1 mL) | 40 units (0.4 mL) | 20 units (0.2 mL) |
| 1.7 mg | 170 units (1.7 mL) | 68 units (0.68 mL) | 34 units (0.34 mL) |
| 2.4 mg | 240 units (2.4 mL) | 96 units (0.96 mL) | 48 units (0.48 mL) |
How the conversion works
Semaglutide is prescribed in milligrams (mg), but a vial is measured in milliliters (mL), and an insulin syringe is marked in units. On a U-100 syringe, 100 units fill 1 mL. So the conversion needs two numbers: the dose you were prescribed, and the concentration printed on your vial.
Units = dose (mg) ÷ concentration (mg/mL) × 100. For example, 0.25 mg from a 2.5 mg/mL vial is 0.1 mL, which is 10 units on a U-100 syringe.
The same dose from a different-strength vial is a different number of units. That is the most common source of dosing errors with compounded vials, and why a number copied from someone else's chart can be wrong for you.
Compounded tirzepatide and semaglutide are not FDA-approved. They are prepared by a licensed pharmacy for an individual patient, and their strength varies from pharmacy to pharmacy, which is exactly why the concentration on your own label is the number that matters. Brand pens (Zepbound, Mounjaro, Wegovy, Ozempic) deliver a fixed dose and need no conversion.
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Answers before you book
How many units is 0.25 mg of semaglutide?
At 2.5 mg/mL it is 10 units, at 5 mg/mL it is 5 units, and at 1 mg/mL it is 25 units on a U-100 syringe. Use the concentration printed on your own vial.
How do I convert semaglutide mg to units?
Divide the prescribed dose in mg by the vial concentration in mg/mL, then multiply by 100. That is the number of units on a U-100 insulin syringe.
Does this calculator tell me what dose to take?
No. It converts a dose your prescriber has already set. Any change to the dose is a decision for your prescriber.
Do Wegovy or Ozempic pens need this conversion?
No. Brand pens deliver a fixed dose. The conversion is only for vials drawn up with a syringe.
Why do small semaglutide doses read as so few units?
Semaglutide doses are small in milligrams, so on a concentrated vial they are only a few units. A lower-strength vial, or a smaller-capacity syringe with finer marks, can make them easier to measure. Ask your pharmacist.
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