Units to mg calculator
Dose (mg) = units ÷ 100 × concentration (mg/mL) on a U-100 syringe. Use it to check what dose a number of units gives you from your vial.
The formula
mL = units ÷ 100 (U-100 syringe) dose (mg) = mL × concentration (mg/mL) dose (mcg) = dose (mg) × 1,000
This is the mg to units calculator run backwards. A unit on an insulin syringe is a fixed volume, 0.01 mL, so the dose it holds depends entirely on how concentrated the liquid is.
Quick reference: units to mg
Each row is a number of units; each column a concentration. Find yours, or use the calculator for any other value.
| Units drawn | 2.5 mg/mL | 5 mg/mL | 10 mg/mL | 20 mg/mL |
|---|---|---|---|---|
| 5 units | 0.125 | 0.25 | 0.5 | 1 |
| 10 units | 0.25 | 0.5 | 1 | 2 |
| 20 units | 0.5 | 1 | 2 | 4 |
| 25 units | 0.625 | 1.25 | 2.5 | 5 |
| 40 units | 1 | 2 | 4 | 8 |
| 50 units | 1.25 | 2.5 | 5 | 10 |
| 75 units | 1.875 | 3.75 | 7.5 | 15 |
| 100 units | 2.5 | 5 | 10 | 20 |
When to use this
People usually come here with a number of units from a clinic handout or a dosing app and want to know what dose that really is. Checking it against your own vial's concentration catches the most common mistake: a chart written for one vial strength being used with another. If the mg you get doesn't match what your prescriber told you, don't inject; call the pharmacy that filled the vial.
For semaglutide and tirzepatide there are ready-made tables: semaglutide units to mg and the tirzepatide dosage chart.
Questions
How do I convert units to mg?
Divide the units by 100 to get mL (U-100 syringe), then multiply by the concentration. 25 units of a 10 mg/mL solution is 0.25 mL × 10 = 2.5 mg.
How many mg is 10 units?
10 units is 0.1 mL. At 2.5 mg/mL that's 0.25 mg; at 5 mg/mL, 0.5 mg; at 10 mg/mL, 1 mg; at 20 mg/mL, 2 mg.
How many mg is 50 units?
50 units is 0.5 mL. At 2.5 mg/mL that's 1.25 mg; at 10 mg/mL, 5 mg; at 30 mg/mL, 15 mg.
Why do two people get different mg from the same units?
Because their vials have different concentrations. Units measure volume, not drug. The label on the vial is the only thing that tells you how much drug is in each unit.