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Litres to gallons converter
Our free tool converts between litres and gallons, so you can see exactly how much fuel it takes to fill your tank
Fuel economy is typically measured by miles to the gallon, but at the fuel pump petrol and diesel is measured in litres. Using our free tool, you can convert between the two so you can more accurately judge your car's fuel economy.
Which? car mpg tests discover a car’s true mpg by using a rolling road in a lab, which means every car can be tested in the exact same way, and the same environment.
The test roads imitate city, out-of-town and motorway driving for extended periods of time - something the official tests don't do - which allows you to see how the mpg could affect your pocket depending on the roads you typically drive on.
Litres to gallons converter
Looking to cut your running costs? We show you how in our money-saving driving tips guide.
Check your petrol prices
Our tests reveal that most official fuel-economy figures are inaccurate.
To discover your car’s true mpg, try using the Which? car fuel calculator. It allows you to work out the amount of fuel you used on recent trips, and see exactly how much you ended up paying for single journeys.
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