Syringe guide

Understanding U-100 Syringes

Learn how U-100 syringe markings correspond to millilitres, including the relationship between 100 units and 1 mL.

What U-100 means

On a U-100 syringe scale, 100 marked units correspond to 1 millilitre of liquid. The markings describe volume on that syringe scale; they do not automatically describe milligrams or micrograms.

100 U-100 syringe units = 1 mL
1 syringe unit = 0.01 mL
Syringe unitsLiquid volume
5 units0.05 mL
10 units0.10 mL
25 units0.25 mL
50 units0.50 mL
100 units1.00 mL

Check the syringe itself

Barrel capacity and marking intervals vary. A 0.3 mL, 0.5 mL and 1 mL U-100 syringe may all use a U-100 scale but display different ranges and increments.

Do not confuse units: syringe-scale units are a volume marking. Product international units are a measure of biological activity. They are not automatically interchangeable.