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Tools / Car & Fuel / Fuel Cost Calculator

Estimate how much fuel a single journey will use and cost. Enter the trip distance, your real-world MPG (miles per gallon), and the fuel price per litre.

Press Enter to move to the next field. On the last field, Enter moves to the result.

Enter the trip distance in miles.
miles
Use a realistic miles-per-imperial-gallon figure from your own driving.
MPG
Enter the pump price in pence per litre.
p
Total fuel cost:
£16.48

A 100 mile journey at 40 MPG uses about 11.4 L of fuel.

Distance100 miles
Litres needed11.4 L
Cost per mile£0.16

* The results provided by this calculator are estimates only. Actual figures may vary based on your inputs, assumptions, costs, rates, taxes, and real-world circumstances. View full disclaimer

How the fuel cost is calculated

The calculator converts your journey distance and fuel efficiency into the number of litres needed. Because UK MPG is based on the imperial gallon, it multiplies the gallons used by 4.54609 to convert that amount into litres.

It then multiplies those litres by your fuel price to give the total journey cost, and divides that total by the distance to show the cost per mile.

Frequently Asked Questions

How do I estimate my car's real MPG (miles per gallon)?
Your dashboard or trip computer can give you a useful starting point, but the best real-world estimate comes from tracking a full tank over normal driving. Use the fuel efficiency figure that reflects your usual mix of city, motorway, and local trips rather than the official brochure number.
Does driving speed affect fuel cost?
Higher motorway speeds, heavy traffic, steep hills, and short stop-start journeys can all lower your real MPG. If you know a trip is mostly town driving or mostly motorway driving, adjust the MPG input to match that route rather than using a single yearly average.
Can I use this for a school run, commute, or road trip?
Enter the distance for any one-off or regular journey to estimate the fuel needed and the total fuel cost. For a return trip, enter the full round-trip mileage.
What if I want to compare two petrol stations instead?
This calculator estimates the cost of one journey. If you want to compare pump prices and see the savings from choosing a cheaper station, try the Petrol Price Savings Calculator.
Have you tried our Petrol Price Savings Calculator?

Compare two petrol prices and see your saving per fill-up, per month, and per year. Includes a breakeven detour distance.

Petrol Price Savings Calculator