Fuel Economy Converter
Convert between mpg, litres per 100 km and km per litre.
What the Fuel Economy Converter does
Fuel economy is measured two opposite ways. Distance per volume (mpg, km/L) means higher is better. Volume per distance (L/100 km) means lower is better. The L/100 km figure is shown separately below because it is an inverse, not a linear conversion.
Formula
Convert to kilometre per litre, then divide by the target unit's factorResult = Value × (from factor ÷ to factor)
Inputs explained
| Input | Unit | Required | Notes |
|---|---|---|---|
| Value | number | Yes | — |
| From | one of 4 options | Yes | — |
| To | one of 4 options | Yes | — |
How to use it
- Choose From and To.
- Enter Value.
- Select Calculate.
Worked example
Convert 15 km/L to US mpg.
- Value
- 15
- From
- km/L
- To
- Miles per US gallon
15 ÷ 0.42514 = 35.28 mpg.
Frequently asked questions
Why is US mpg lower than UK mpg for the same car?
The imperial gallon is 20% larger, so the same car travels further on one imperial gallon. A 30 US mpg car is 36 UK mpg.
How do I convert to L/100 km?
Divide 100 by the km/L figure. 15 km/L is 6.67 L/100 km.