Gas Mileage Calculator
Find your fuel economy from distance and fuel used.
Know your true fuel economy
Your car’s trip computer estimates fuel economy, but the real figure comes from miles driven divided by the fuel it actually took. This calculator gives you that, in both imperial and metric.
Enter the miles covered and the gallons used at the next fill-up. Three hundred miles on twelve gallons is 25 miles per gallon, which it also shows as kilometres per litre and litres per 100 kilometres.
Accurate and private
The calculation runs in your browser, so nothing you enter is uploaded.
Frequently Asked Questions
How is mileage calculated?
Miles driven divided by gallons used gives miles per gallon. The tool also converts to metric economy figures.
What metric figures does it show?
Kilometres per litre and litres per 100 kilometres, the standard European economy measure.
How do I get an accurate reading?
Fill up, reset the trip meter, drive, then refill and note the gallons — that fuel is what powered those miles.
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