What is the difference between a 0.5 mL and a 1 mL insulin syringe?
On U-100, both use the same unit: 1 unit = 0.01 mL. A 0.5 mL syringe holds 50 units and a 1 mL syringe holds 100 units. The 0.5 mL barrel usually marks every unit; the 1 mL barrel often marks every 2 units, so small amounts are easier to read on the smaller barrel.
The math
0.5 mL × 100 = 50 units 1 mL × 100 = 100 units mL = units ÷ 100 on both
| Syringe | U-100 capacity | Typical line spacing |
|---|---|---|
| 0.3 mL | 30 units | 1 unit |
| 0.5 mL | 50 units | 1 unit |
| 1 mL | 100 units | 2 units |
Math only, not medical advice. This page converts numbers; it does not recommend any compound or amount.
Draw to
10 units
= 0.1 mL · concentration 2.5 mg/mL (2500 mcg/mL) · 20 draws per vial
Concentration = 5 mg ÷ 2 mL = 2.5 mg/mL Volume = 250 mcg ÷ 2500 mcg/mL = 0.1 mL Units = 0.1 mL × 100 (U-100) = 10 units
Math only, not medical advice. Verify every number yourself.