Fuel calculator

Fuel prices are as high as ever, so it’s important to make sure you’re getting cheap fuel — and plenty of miles for your money. 

Our simple fuel calculator lets you check how efficient your car really is — and whether it matches the manufacturer’s claimed fuel economy figures.

You can also use it to calculate the cost of individual journeys, which will help you decide whether you should take the car or opt for a cheaper mode of transport in future.

To get started, just enter the amount you paid for a litre of fuel when you last filled up. Then, enter the amount of fuel you purchased (in litres) and the total number of miles you covered with that fuel. 

You’ll then be presented with two figures, one showing the total cost of your journey and another showing your car’s fuel economy in miles per gallon (mpg).

If your car has a trip computer, be wary of the economy figure displayed. It's often inaccurate, so it's a good idea to get into the habit of resetting your odometer (mileometer or trip meter) after every fill. 

That way, you can record your mileage and the amount of fuel used at the next fill-up. Simply enter both figures into the fuel calculator to find out your true fuel economy.

What next?

If you’re surprised by how much you’re paying for car journeys, consider shopping around for cheaper fuel. Our free guide to finding the cheapest fuel shows you how you can find the cheapest petrol, diesel and LPG in your area, and offers helpful advice on fuel-efficient driving.

To get even more miles for your money, why not trade in your present model for a greener car? The top performers, listed in our greener car review, claim to offer anything up to 74 miles per gallon.

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