How to convert miles per US gallon to liters per 100 km
1 mpg (US) = 235.215 L/100 km
L/100 km = 235.215 ÷ US mpg (NIST SP 811 B.9). The constant comes from the exact mile and US gallon: 235.2145833… Lower L/100 km means less fuel.
Examples
- 25 mpg (US) = 9.4085833 L/100 km: A car rated in US mpg
- 30 mpg (US) = 7.8404861 L/100 km: A sedan rated in US mpg
- 50 mpg (US) = 4.7042917 L/100 km: A hybrid rated in US mpg
Mpg to L/100 km chart
| Miles per US gallon (mpg (US)) | Liters per 100 km (L/100 km) |
|---|---|
| 10 mpg (US) | 23.521458 L/100 km |
| 15 mpg (US) | 15.680972 L/100 km |
| 20 mpg (US) | 11.760729 L/100 km |
| 25 mpg (US) | 9.4085833 L/100 km |
| 30 mpg (US) | 7.8404861 L/100 km |
| 35 mpg (US) | 6.7204167 L/100 km |
| 40 mpg (US) | 5.8803646 L/100 km |
| 50 mpg (US) | 4.7042917 L/100 km |
Common mistakes
- There is no fixed multiplier: doubling mpg halves L/100 km.
- Equal mpg gains are not equal savings: going from 10 to 20 mpg saves about 11.8 L/100 km, but 30 to 40 mpg saves about 2.0 L/100 km.