Toolstia / fuel economy converter
Fuel economy converter
Convert fuel economy between US mpg, UK mpg, kilometres per litre and litres per 100 kilometres. Note that litres per 100 km works the opposite way round: a smaller number is more efficient.
| Unit | 1 Miles per US gallon (mpg) equals |
|---|---|
| Litres per 100 km | 235.214583333 |
| Kilometres per litre | 0.42514370743 |
| Miles per US gallon (mpg) | 1 |
| Miles per UK gallon (mpg) | 1.2009499255 |
How it works
- Type the value.
- Choose the unit you are converting from and the unit you want.
- Read the result, and scan the table for every other unit at once.
Why the numbers look so different
US mpg uses the US gallon (3.785 l) and UK mpg the larger imperial gallon (4.546 l), so the same car has a higher UK mpg figure. 30 US mpg is about 36 UK mpg.
Inverse units
Litres per 100 km measures fuel used per distance, while mpg and km/L measure distance per fuel. Converting between them uses a reciprocal, such as L/100 km = 235.215 ÷ mpg (US).
Examples
30 mpg (US) is about 7.84 L/100 km. 8 L/100 km is about 29.4 mpg (US) or 35.3 mpg (UK).
Zero
Zero mpg is not a meaningful fuel economy, so the tool asks for a value above zero. Zero is only allowed in litres per 100 km.
Questions
Which is better, a high or low L/100 km?
Low. It means less fuel per 100 km.
Is UK mpg the same as US mpg?
No. The UK gallon is larger, so UK mpg numbers are about 20% higher.
Is anything uploaded?
No. The conversion happens in your browser and nothing is sent anywhere.