About Fuel Price Calculator

Last updated: 3 October 2026

Fuel Price Calculator helps UK drivers estimate what a journey will cost before they set off. Enter a driving route or mileage, choose a fuel price, and use your car's real-world fuel economy to calculate fuel needed and cost per mile.

Fuel Price Calculator is operated by Impact SEO, a UK sole-trader business. For service enquiries, privacy requests or complaints, email info@impactseo.co.uk or call 01603 339 110.

How the calculation works

For imperial MPG, litres needed = miles ÷ UK MPG × 4.54609. Multiply the litres by the fuel price in pounds per litre to estimate fuel cost. US MPG uses 3.785411784 litres per gallon. Litres/100km is converted using 1 mile = 1.609344 kilometres.

Example

At 45 UK MPG, a 100-mile journey uses about 10.10 litres. If fuel is 145p per litre, it costs about £14.65. Parking and tolls are separate costs. Calculations use unrounded values internally and round the displayed result.

Where the information comes from

UK weekly fuel averages come from the Department for Energy Security and Net Zero. Postcodes.io supplies postcode coordinates, Photon/OpenStreetMap supplies place and station information, and OSRM supplies estimated driving distances. You can always enter the miles and pump price yourself if a data service is unavailable.

What is not included

The first version does not provide live station prices, traffic-aware routing, EV charging costs, vehicle-specific MPG lookup, breakdown advice or a fuel-purchase service. Fuel cost is only one part of driving costs; insurance, tax, maintenance and depreciation are not included unless you deliberately add a cost to your estimate.