Fuel economy converter (mpg, L/100 km and km/L)
Convert fuel economy between miles per US gallon (mpg US), imperial gallon (mpg UK), km/L and liters per 100 km, handy for comparing cars and tests from other countries.
Fuel economy conversion
Everything happens on your device: nothing is uploaded to the internet.
1 mile = 1.609344 km · 1 US gallon = 3.785411784 L · 1 UK gallon = 4.54609 L.
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Fuel economy converter (mpg, L/100 km and km/L): what it is for
Type the fuel economy in any unit and see the value in kilometers per liter, liters per 100 km, miles per US gallon, miles per imperial gallon and miles per liter, plus how many liters the car uses in 1,000 km. Useful for comparing imported cars and reviews from foreign magazines.
The conversion is done in your browser.
How to use
- Type the fuel economy.
- Choose the unit.
- See every conversion.
When to use it
- Comparing fuel economy of US and European cars.
- Understanding spec sheets in L/100 km.
- Converting data from travel apps.
Frequently asked questions
How do I convert mpg to L/100 km?
Divide 235.215 by the mpg (US). A car that gets 30 mpg uses about 7.8 L/100 km. For km/L, divide 100 by the L/100 km: 100 ÷ 8 = 12.5 km/L.
What is the difference between mpg US and mpg UK?
The US gallon is 3.785 liters and the British imperial gallon is 4.546 liters. That's why the same car has a higher mpg in the British standard.
Why does L/100 km seem backwards?
Because it measures how much fuel is used for a fixed distance: the lower the number, the more efficient the car. With km/L and mpg, higher is better.
Is it really free?
Yes, 100% free. No sign-up, no subscription and no usage limits. All Tools123 tools are free and run right in your browser.