Convert your fuel economy between kilometres per litre, litres per 100 km, and miles per gallon. Enter one figure, choose its unit, and the converter shows the other three. Use it to enter the right number in our fuel cost calculators, which ask for kilometres per litre.
The converter only changes units. It does not suggest a fuel economy for any vehicle.
Higher km/l and mpg mean better economy. Lower L/100 km means better economy.
Nothing you type is stored or sent anywhere.
How the conversions work
- Litres per 100 km = 100 ÷ kilometres per litre
- Miles per US gallon = kilometres per litre × 3.785411784 ÷ 1.609344
- Miles per UK gallon = kilometres per litre × 4.54609 ÷ 1.609344
The constants are 1 mile = 1.609344 km, 1 US gallon = 3.785411784 litres and 1 UK gallon = 4.54609 litres. US and UK gallons are different sizes, so the two mpg figures differ for the same vehicle.
Worked example (made-up number, not a vehicle’s mileage)
A figure of 40 km per litre is the same as 2.5 litres per 100 km, about 94.09 US mpg or about 112.99 UK mpg. The example only shows how the units relate. It is not a claim about any bike or car.
Use the result in our calculators
- Measure your own mileage and work out monthly fuel cost with the petrol cost and mileage calculator.
- Plan a journey with the trip fuel cost calculator.
- See every monthly cost of a vehicle with the vehicle ownership cost calculator.
Fuel economy converter FAQs
How do I convert km per litre to litres per 100 km?
Divide 100 by your km per litre. The converter does this for you.
Why are US and UK mpg different?
The US gallon (3.785 litres) is smaller than the UK gallon (4.546 litres), so the same vehicle has a higher mpg figure in UK gallons.
Which figure do the other calculators on this site need?
Our fuel cost calculators ask for kilometres per litre. Convert your figure here first if you know it in another unit.
Does this tell me my vehicle’s fuel economy?
No. It only converts the number you enter. To measure your own economy, use the full-tank method on the petrol cost calculator.