Estimate petrol or diesel cost for one journey, repeated trips and each passenger’s share.
Estimate only. Real consumption varies with traffic, speed, weather, vehicle load, tyre pressure, driving style and route conditions.
How to use the Fuel Cost Calculator UK
Enter the journey distance, your vehicle’s UK MPG, the current pump price in pence per litre, the number of journeys and the number of people sharing the bill. Use the full travelled distance, including the return leg when applicable.
How fuel cost is calculated
| Result | Calculation |
|---|---|
| Total distance | Distance per journey × number of journeys |
| Imperial gallons used | Total miles ÷ UK MPG |
| Litres used | Imperial gallons × 4.54609 |
| Total fuel cost | Litres × price per litre |
| Cost per person | Total fuel cost ÷ people sharing |
UK MPG and litres
UK MPG uses the imperial gallon, equal to approximately 4.54609 litres. This differs from the smaller US gallon, so an American MPG figure should not be entered without conversion. A lower real-world MPG increases the estimated fuel requirement and cost.
Finding a realistic MPG figure
The official combined MPG can be a useful reference, but real-world consumption may differ. For a more personal estimate, divide miles driven between fill-ups by the imperial gallons added. Use several normal journeys to reduce the effect of one unusual trip.
Using the correct pump price
Fuel prices change frequently and vary by location. Enter the forecourt price in pence per litre rather than pounds. For example, £1.459 per litre should be entered as 145.9. The UK government publishes weekly road fuel price statistics for petrol and diesel.
What the estimate excludes
The result covers fuel only. It does not include vehicle depreciation, finance, insurance, tax, servicing, tyres, parking, tolls or congestion charges. Those costs can be important when comparing the full cost of different travel choices.
Related calculators
Compare finance and running commitments with the Car Lease Cost Calculator UK. If you need to calculate fuel economy from distance and litres, use the MPG Calculator UK. Browse all tools on the United Kingdom Calculator homepage.
Frequently asked questions
Should I enter UK or US MPG?
Enter UK MPG based on the imperial gallon. US MPG uses a smaller gallon and will produce an incorrect result here.
Do I enter fuel price in pounds or pence?
Enter pence per litre. A pump price of £1.459 per litre is entered as 145.9.
How do I calculate a return journey?
Enter the complete outward-and-return distance as one journey, or enter the one-way distance and use 2 journeys.
Why might actual fuel cost be higher?
Congestion, cold starts, high speed, hills, heavy loads and lower real-world MPG can increase fuel use.
Does this include parking and tolls?
No. It estimates fuel cost only, so add parking, tolls and other journey charges separately.