20 units in mL on a U-100 syringe
20 marked units on a U-100 syringe represent 0.20 mL.
Volume arithmetic only. This is not a recommended amount, an insulin dose calculation or a biological IU conversion.
The same markings represent the same volume on every U-100 barrel. Capacity and line spacing are separate checks. The 0.20 mL example is within all three illustrated barrel capacities.
Load 20 markings in the calculator and choose your actual syringe →
Compare the three barrel capacities
0.3 mL barrel · 30 units
0.20 mL is within capacity. Illustration uses 1-unit divisions.
The pointer follows the exact result. A position between lines is not a marked division.
0.5 mL barrel · 50 units
0.20 mL is within capacity. Illustration uses 1-unit divisions.
The pointer follows the exact result. A position between lines is not a marked division.
1 mL barrel · 100 units
0.20 mL is within capacity. Illustration uses 2-unit divisions.
The pointer follows the exact result. A position between lines is not a marked division.
Nearest-mark comparison
These are example scale options. Check the packet and barrel; capacity does not guarantee a particular graduation. A nearest mark is a comparison, not permission to change an amount.
| Barrel | Division | Nearest mark | Difference |
|---|---|---|---|
| 1 mL | 2 units | 20 units | 0% |
| 1 mL | 1 units | 20 units | 0% |
| 0.5 mL | 1 units | 20 units | 0% |
| 0.3 mL | 1 units | 20 units | 0% |
| 0.3 mL | 0.5 units | 20 units | 0% |
Keep the units distinct
U-100 markings describe volume in this example. The mass in mg or mcg depends on the solution concentration. A different syringe scale needs different arithmetic. Confirm measurement instructions with your pharmacist or prescriber.
Device context checked against the BD Getting Started booklet, 17 October 2026. The conversion is derived from the U-100 scale. No clinical endorsement is claimed.