Journey fuel cost calculator
Car running costs calculator
Or work it out with your own figures:
Your car's running costs estimate
MPG calculator: your car's real fuel economy
Brim the tank and reset the trip meter. At the next fill-up, brim it again and enter the miles and litres.
How the fuel cost calculator works
A UK gallon is 4.546 litres, so a car's fuel cost per mile is price per litre × 4.546 ÷ mpg. At 174.2p a litre and 45 mpg, that is about 18p a mile. For an electric car it is price per kWh ÷ miles per kWh: at the Ofgem cap rate of 26.32p and 3.3 miles per kWh, about 8p a mile.
The fuel prices filled in are the Fuel Finder UK average today (2026-10-18). Prices near you can be several pence higher or lower: find them with our cheapest fuel near me search, and see the trend on the UK fuel prices page.
What does it cost to run a car in the UK?
For an average car the biggest costs are usually depreciation, fuel and insurance. With the published averages above (7,100 miles a year, a 45 mpg petrol car, the average insurance premium, one service and an MOT), running costs come to about £2,330 a year (33p a mile) before depreciation, tyres and finance. Your own figures will differ, which is why every field can be changed.
| Cost | Typical figure | Source |
|---|---|---|
| Insurance | £566 a year | ABI, average premium paid, Apr to Jun 2026 |
| Road tax | £200 a year | GOV.UK, standard rate for cars from April 2017; older cars by CO2 band (car tax calculator) |
| Service | £260 to £361 | Which? 2025 survey: independent garage and main dealer |
| MOT | Up to £54.85 | GOV.UK maximum fee for a car |
| Home charging | 26.32p per kWh | Ofgem price cap, Oct to Dec 2026 |
| Public charging | 54p (slow/fast), 79p (rapid) per kWh | Zapmap Price Index, Sep 2026 |
| Miles a year | 7,100 | DfT National Travel Survey 2025, England |
Find out a used car's real running costs before you buy
Every free car check now includes a running costs estimate for that car: its average mileage from the MOT history, fuel economy estimated from its official CO2 figure, today's fuel price and its road tax at GOV.UK rates. See car running costs by reg for how it works. The full report adds the manufacturer's mpg figures and the road tax recorded for the car, together with outstanding finance, write-off and stolen checks. Related: fuel type check, car tax calculator, MOT history check, car spec check and our car depreciation calculator.
Buying a used car? Check it first
Our free check shows the MOT history, mileage readings and tax status. The full report adds outstanding finance, insurance write-offs, stolen markers, previous keepers and the car's mpg, fuel type and road tax cost.
See what the full report covers in the sample car history report.
Frequently asked questions
How do I calculate the fuel cost of a journey?
Divide the distance by your car's mpg to get gallons, multiply by 4.546 to get litres, then multiply by the price per litre. For 100 miles at 45 mpg and 175p a litre: 100 / 45 x 4.546 = 10.1 litres, which costs about £17.68.
How much does it cost to run a car in the UK?
It depends most on fuel, insurance and depreciation. Enter your own figures in the running costs calculator above: it adds fuel or charging, road tax, insurance, servicing, MOT, tyres, depreciation and finance, and shows the cost a year, a month and a mile.
How do I work out my car's real mpg?
Fill the tank to the brim and reset the trip meter. At the next fill-up, brim the tank again and note the litres and the miles driven. Miles divided by (litres / 4.546) is your real mpg. The mpg calculator above does the sum.
Is an electric car cheaper to run than petrol?
Charging at home usually is. At the Ofgem price cap rate of 26.32p per kWh and 3.3 miles per kWh, an electric car spends about 8p a mile on electricity, against about 18p for a 45 mpg petrol car at 175p a litre. Public rapid charging (about 79p per kWh) can cost as much as petrol or more.
What is the cost per mile of driving?
Fuel alone is usually 12p to 25p a mile for a petrol or diesel car. With insurance, tax, servicing and depreciation, the total cost per mile is often several times that, which is why the running costs calculator shows both.
How many litres are in a gallon?
A UK (imperial) gallon is 4.546 litres. US mpg figures use the smaller US gallon (3.785 litres), so they look lower for the same car.