Journey distance
Use the one-way or total distance depending on the trip you want to cost.
Journey cost—
Enter your details to calculate.
UK fuel cost & journey calculator
Work out the petrol or diesel cost of a journey from distance, UK MPG and pump price per litre. The calculator is useful for trip costs, commuting, mileage planning and comparing how much different vehicles cost to run.
Fuel economy
Higher MPG means the vehicle uses less fuel for the same journey.
Fuel price
Enter the current pump price in pence per litre for a more useful estimate.
Worked example: petrol cost for a journey
For a 150-mile journey in a car returning 45 UK MPG with petrol at 145p per litre, the calculator converts imperial gallons to litres, works out the fuel used and multiplies it by the pump price. Change the number of journeys to price a return trip or repeated commute.
Formula: miles ÷ UK MPG × 4.54609 litres per imperial gallon × price per litre.
Frequently asked questions
Does this use UK MPG?
Yes. The calculator is designed around imperial gallons used for UK MPG figures.
Can I calculate a return journey?
Yes. Either double the distance or increase the number of journeys.
Why is my real fuel cost different?
Driving speed, traffic, temperature, tyres and vehicle load can all affect real fuel economy.
Built for quick, transparent estimates. See how our calculators work and check page-specific assumptions before relying on a result.