Trip & fuel cost calculator

How to use this tool

1. Enter the distance and choose kilometres or miles. Tick round trip to double it.
2. Enter your car's efficiency and pick its unit: L/100 km, km/L, US MPG or UK MPG.
3. Enter the fuel price and whether it is per litre or per gallon.
4. Add the number of people to split the cost, then read the fuel needed, the total cost and the cost per km and per mile.

How it works

Everything is converted to litres and kilometres first, so you can mix units freely, for example a distance in miles, an efficiency in L/100 km and a price per US gallon. Fuel needed is the distance times the consumption. Cost is the fuel times the price per litre.

Litres = km × (L per 100 km) ÷ 100
From MPG: litres = miles ÷ MPG × litres per gallon (3.785 US, 4.546 UK)
Cost = litres × price per litre

Good to know

US and UK gallons are different sizes. A UK gallon is about 20% larger, so 40 mpg in the UK is roughly 33 mpg in the US. Check which one your car's figure uses. If you only know the L/100 km figure, a quick conversion is 235 divided by the L/100 km for US MPG.

The result uses a steady consumption figure. Motorway speeds, heavy loads, roof boxes, air conditioning and cold weather all raise it. For a more cautious estimate add 10 to 15 percent. Tolls, parking and wear on the car are not included. Use the share field for car pools and road trips. The currency selector only changes the symbol and number format.