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Driver calculators & tools

Petrol vs diesel calculator

By Martin Pratt

Article 1 of 4

Put us to the test

Our Test Labs compare features and prices on a range of products. Try Which? to unlock our reviews. You'll instantly be able to compare our test scores, so you can make sure you don't get stuck with a Don't Buy.

Petrol vs diesel calculator

Does buying diesel really save you money? Or is petrol the better buy? Here's our fuel cost calculator to help you choose the right engine for your car.

Want to win £2,500?

The 2019 Which? Car Survey is now open and we need your help. Tell us about the car and not only will you be helping us shape our reviews and knowledge about the nation's cars, but you will also be in with a chance of winning enough money to fuel your car for an entire year.

To take part in the survey, click here.

Petrol vs diesel fuel cost calculator: is the diesel premium worth it?

Our fuel-cost calculator lets you quickly work out the annual fuel costs between two cars (petrol and diesel, or otherwise). Firstly, click the Add another car for comparison option, then add the fuel economy figures for two cars and your annual mileage (most Which? members drive about 9,000 miles each year). Current fuel prices can be looked up on sites such as the AA (theaa.com/motoring_advice/fuel), PetrolPrices.com - or check your local garage.

But there's more to consider than just fuel costs. For the full lowdown on whether you should invest in a petrol or diesel car, here's our dedicated guide on how to choose between petrol and diesel.