Working out whether a diesel- or a petrol-powered car will be cheaper to run over three years is a complicated business.
To ensure you're making the most cost-effective decision you have to consider the higher purchase cost as well as resale values, fuel bills, servicing and insurance bills.
Let the facts do the talking
To help make the job a little easier, we've developed a tool to do the sums for you.
Fill in the boxes and the calculator will tell you the most cost-effective option based on your individual circumstances.
Download our petrol vs diesel calculator
Download the petrol vs diesel calculator (pc version)
Don't forget you can find all of the data you need by looking at the reviews of the cars you're considering.
Compare the cars
You can even run a comparison of two cars such as this.