Gas mileage calculator
Work out your fuel economy from distance and fuel used, and convert between mpg, litres per 100 km and km per litre.
About this calculator
Enter the distance driven and the fuel used to get miles per gallon (US and UK), litres per 100 km and kilometres per litre. Add the fuel price to see the cost per mile.
The second panel converts any fuel economy figure into the other units.
Measurements and terms explained
- mpg (US)
- Miles per US gallon of 3.785 litres.
- mpg (UK)
- Miles per imperial gallon of 4.546 litres.
- L/100 km
- Litres of fuel used to travel 100 kilometres. A lower number is better.
- km/L
- Kilometres travelled on one litre of fuel. A higher number is better.
Common questions
Why are US and UK mpg different?
The UK gallon is larger, 4.546 litres against 3.785 litres, so the UK figure is about 20% higher.
How do I get the most accurate figure?
Fill the tank, drive, then fill up again. Divide the distance by the fuel added.
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