Wegovy is the weight-management brand of semaglutide, delivered in fixed-dose prefilled pens — so the pen itself needs no math. This page explains the Wegovy dose schedule, then gives you the calculator you do need if you are working from a compounded semaglutide vial instead of a pen.
Last reviewed against the Wegovy prescribing information.
What is the Wegovy dose schedule?
Wegovy pens are prefilled at a fixed weekly dose, so there is nothing to measure — you select the pen for your current step. The label's titration starts low and steps up roughly every four weeks to let tolerability catch up.
Because each pen delivers a set amount, you never reconstitute or draw a Wegovy pen. The math only appears when you switch to a compounded vial.
- Standard weekly steps: 0.25 → 0.5 → 1.0 → 1.7 → 2.4 mg
- Each step is typically held about 4 weeks before increasing
- Pens are fixed-dose — no reconstitution or syringe-unit math
How is a compounded semaglutide vial different from a Wegovy pen?
Compounded semaglutide is supplied as a vial of solution or lyophilised powder, not a prefilled pen. That means you have to convert vial strength and bacteriostatic water volume into a concentration, then work out the draw volume and syringe units for your target dose — exactly the math a pen hides.
If you are on Wegovy pens, you do not need the calculator. If you are on a compounded vial dosed to match the same schedule, use the semaglutide calculator below to turn each step into units on your syringe.
- Pen = fixed dose, no math
- Compounded vial = you calculate concentration, draw volume, and units
- The dose targets can match; only the measuring differs
Wegovy calculator: compounded semaglutide units for each dose step
The Wegovy pen itself is fixed-dose, so a “Wegovy calculator” is really a compounded semaglutide calculator: units = dose (mg) ÷ concentration (mg/mL) × 100 on a U-100 syringe.
At 2.5 mg/mL (a 5 mg vial mixed with 2 mL of bacteriostatic water), each Wegovy step works out as below. A different vial or water volume changes every number, so run your own vial in the calculator above.
- 0.25 mg = 0.1 mL = 10 units
- 0.5 mg = 0.2 mL = 20 units
- 1.0 mg = 0.4 mL = 40 units
- 1.7 mg = 0.68 mL = 68 units
- 2.4 mg = 0.96 mL = 96 units
Compounded semaglutide reference
U-100 units to draw for each common Semaglutide dose, by vial size, reconstituted with 2 mL of bacteriostatic water. Change the water volume in the calculator above to recompute for your own setup.
| Vial | Concentration | 250 mcg | 500 mcg | 1 mg | 1.7 mg | 2.4 mg |
|---|---|---|---|---|---|---|
| 2.5 mg | 1.25 mg/mL | 20 u(0.2 mL) | 40 u(0.4 mL) | 80 u(0.8 mL) | 136 u(1.36 mL) | 192 u(1.92 mL) |
| 5 mg | 2.5 mg/mL | 10 u(0.1 mL) | 20 u(0.2 mL) | 40 u(0.4 mL) | 68 u(0.68 mL) | 96 u(0.96 mL) |
| 10 mg | 5 mg/mL | 5 u(0.05 mL) | 10 u(0.1 mL) | 20 u(0.2 mL) | 34 u(0.34 mL) | 48 u(0.48 mL) |
Swipe the table to see every dose →
Educational reference only — not a dose recommendation. Units assume a U-100 insulin syringe (100 units = 1 mL on U-100). Always confirm against your own vial, diluent, and clinician or pharmacy instructions.
Frequently asked questions
Do I need a calculator for Wegovy?
What are the Wegovy dose steps?
Is compounded semaglutide the same as Wegovy?
How many units is the first Wegovy dose from a compounded vial?
Primary sources
The Wegovy label for the pen dose schedule, and the FDA's warning on dosing errors with compounded GLP-1 vials. PepSync makes no clinical claims.