Fuel economy converter
This converter changes fuel economy figures between the units used in different countries. It handles US miles per gallon, UK (Imperial) miles per gallon, liters per 100 km and kilometers per liter. Car buyers and travelers use it to compare vehicles rated in different units.
- Runs in your browser
- Free, no account needed
- Copy or download the result
Result
Example
30 25 42.5
30 mpg US = 36.03 mpg UK, 7.84 L/100 km, 12.75 km/L 25 mpg US = 30.02 mpg UK, 9.41 L/100 km, 10.63 km/L 42.5 mpg US = 51.04 mpg UK, 5.53 L/100 km, 18.07 km/L Higher mpg and km/L are better; lower L/100 km is better. A UK gallon (4.546 L) is larger than a US gallon (3.785 L).
How to use the fuel economy converter
- Type one value per line, such as 30.
- Choose the From unit.
- Choose the To unit, or All units to see every conversion.
- Press Run, then use Copy result or Download.
How it works
Conversions use 1.609344 km per mile, 3.785411784 liters per US gallon and 4.54609 liters per UK gallon.
L/100 km is the inverse of km per liter: 100 divided by km/L. So a higher mpg means a lower L/100 km.
Values must be greater than zero. Up to 100 lines are allowed and results show two decimal places.
Everything runs in your browser. Your input is not uploaded or stored.
Questions and answers
How do I convert mpg to L/100 km?
Divide 235.215 by the US mpg value. 30 mpg US is about 7.84 L/100 km.
Why are UK mpg numbers higher than US mpg?
A UK gallon is about 4.546 liters and a US gallon is about 3.785 liters, so a car goes farther on a UK gallon.
Is a lower L/100 km better?
Yes. L/100 km measures fuel used per distance, so a lower number means the car uses less fuel.