Units to mg chart (U-100 syringe)
The same units are a different number of mg at each strength. Find your strength (mg per mL, from your vial) and read across:
| Units | at 2.5 mg/mL | at 5 mg/mL | at 10 mg/mL |
|---|---|---|---|
| 5 units | 0.125 mg | 0.25 mg | 0.5 mg |
| 10 units | 0.25 mg | 0.5 mg | 1 mg |
| 20 units | 0.5 mg | 1 mg | 2 mg |
| 25 units | 0.625 mg | 1.25 mg | 2.5 mg |
| 50 units | 1.25 mg | 2.5 mg | 5 mg |
| 100 units | 2.5 mg | 5 mg | 10 mg |
25 units to mg, 50 units to mg and 10 units to mg
At 10 mg/mL, 25 units is 2.5 mg, 50 units is 5 mg and 10 units is 1 mg. At 5 mg/mL those are 1.25 mg, 2.5 mg and 0.5 mg. Going the other way? Read how many units is 2.5 mg.
The conversion
On a U-100 insulin syringe, 100 units fill 1 mL. So units are just hundredths of a millilitre, and the drug in them depends on the concentration:
mL = units ÷ 100
mg = mL × concentration (mg/mL)
units = mg ÷ concentration × 100
Worked examples
- A 10 mg/mL vial: 25 units = 0.25 mL = 2.5 mg.
- A 10 mg vial mixed with 2 mL (5 mg/mL): 20 units = 0.2 mL = 1 mg.
- To draw 250 mcg from a 5 mg/mL vial: 0.25 ÷ 5 × 100 = 5 units.
Before you rely on a chart
- Check the concentration on your own vial. Compounded vials of the same drug come in different strengths.
- Check your syringe says U-100.
- Don’t know your concentration because you mixed the vial yourself? Enter the vial size and water, or use the peptide calculator.
Questions
How many mg is 25 units?
25 units on a U-100 syringe is 0.25 mL. At 10 mg/mL that is 2.5 mg, at 5 mg/mL it is 1.25 mg and at 2.5 mg/mL it is 0.625 mg. See the units to mg chart above. For the reverse, see how many units is 2.5 mg.
How many mg is 10 units?
10 units on a U-100 syringe is 0.1 mL. How many mg that is depends on the concentration: at 5 mg/mL it is 0.5 mg, at 10 mg/mL it is 1 mg, at 2.5 mg/mL it is 0.25 mg. Units measure volume, not amount of drug.
How do I convert tirzepatide or semaglutide units to mg?
Multiply the units by 0.01 to get mL, then multiply by the concentration on your vial (mg/mL). For a 10 mg/mL vial, 25 units = 0.25 mL = 2.5 mg. For a 2.5 mg/mL vial, 25 units = 0.625 mg. Always use the concentration printed on your own vial.
Why do different charts give different mg for the same units?
Because they assume different concentrations. A units-to-mg chart is only correct for one concentration, which is why this converter builds the chart from yours.
What does U-100 mean?
The syringe is marked for 100 units per mL, so 1 unit = 0.01 mL. Almost all insulin syringes sold in the US are U-100. If yours is marked U-40 or U-50, these numbers do not apply.