Semaglutide Dose Calculator

Compounded semaglutide comes as a liquid in a vial with a concentration printed on the label, in milligrams per milliliter. Doses are drawn with a U-100 insulin syringe, whose markings are a volume scale: 100 units is 1 mL, so each unit is 0.01 mL. Converting a dose is one line of arithmetic: divide the dose in mg by the concentration in mg/mL to get milliliters, then multiply by 100 to get units.

The same draw holds a different amount of medication at a different concentration, which is the whole reason the concentration field comes first. 25 units is 2.5 mg from a 10 mg/mL vial and 5 mg from a 20 mg/mL vial. If you were switched to a new vial, a new pharmacy, or a different strength, re-run the number rather than reusing last month's units.

It does not choose or adjust a dose. Dose escalation for these medications follows the label ladder and your prescriber's judgement; the dose chips on the calculator are the label strengths for reference only. It also does not apply to the branded pens: Zepbound, Mounjaro, Wegovy, and Ozempic pens deliver a set dose without any unit conversion, and the Zepbound single-dose vials are drawn in full as their instructions describe.

Compounded GLP-1 products are not FDA-approved, and the FDA has received reports of dosing errors with compounded injections, including confusion between units and milligrams. Those reports are the reason this page exists: check the math, then confirm it with the pharmacy that dispensed your vial. Compounded semaglutide and tirzepatide are a US-only option.

The same label ladder at the concentrations pharmacies most often dispense. Cells over 100 units do not fit a single 1 mL insulin syringe. Read the mg/mL on your own vial and use that column; the calculator above handles any other concentration.

The units are the easy part to lose track of. What matters over a course of treatment is the record: which mg dose you took, on which day, in which injection site, and what happened afterwards. GlucoPal logs compounded tirzepatide and semaglutide by mg dose alongside the branded pens, sends a reminder for the weekly draw, keeps an injection-site rotation map, and turns the history into a doctor-ready PDF for your next appointment.

It is free to download and use, with no account required, and it keeps this calculator company: work out the draw here, log the dose there.

The Wegovy label escalates every four weeks: 0.25 mg, 0.5 mg, 1 mg, 1.7 mg, then the 2.4 mg maintenance dose (with a 7.2 mg Wegovy HD strength available in the pen). Compounded semaglutide prescriptions usually follow the same ladder. At 2.5 mg/mL the five steps are 10, 20, 40, 68, and 96 units, all within a 1 mL syringe. At 5 mg/mL they are 5, 10, 20, 34, and 48 units; at 1 mg/mL the 2.4 mg dose alone is 240 units, which no single insulin syringe holds.

Ozempic's label doses (0.25, 0.5, 1, and 2 mg) convert the same way; the calculator's dose field accepts any value, and the chips are the Wegovy strengths for reference.

Compounded vial labels vary. Some state a concentration (2.5 mg/mL), some state a total and a volume (5 mg/2 mL, which is the same 2.5 mg/mL), and some pharmacies print the dose in units directly on the prescription label. If your label gives a total and a volume, divide the first by the second to get mg/mL. If it gives units, the calculator lets you check that the units, the concentration, and the milligram dose on your prescription agree.

Many compounded semaglutide vials also contain vitamin B12 or other additives; those do not change the arithmetic, which depends only on the semaglutide mg/mL. Compounded semaglutide is a US-only option, is not FDA-approved, and the FDA has flagged unit-versus-milligram confusion as a source of dosing errors, which is exactly the mistake this page is built to catch.

The Wegovy pen is a fixed-dose, single-use pen: the strength is printed on it and there is nothing to draw. The Ozempic pen is multi-dose and dialed to the dose in milligrams, not units. Neither involves an insulin syringe, so this calculator only applies to compounded semaglutide in a vial, or to a powder you reconstitute yourself, where the concentration is the mg of powder divided by the mL of water added.