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Fuel Cost Calculator

Work out how much a trip will cost in fuel — in kilometers or miles, liters or gallons — and split it between passengers.

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How to use Fuel Cost Calculator

  1. 1Enter the trip distance in kilometers or miles.
  2. 2Enter your car's fuel economy in L/100 km, km/L, US mpg or UK mpg.
  3. 3Enter the fuel price per liter, per US gallon or per UK gallon.
  4. 4Tick Round trip to double the distance and set the number of people to split the cost.

How much will the trip cost?

Planning a road trip, a daily commute or a move? Fuel is often the biggest running cost. This calculator estimates the fuel needed and its cost from three numbers you know: the distance, your car's fuel economy and the price of fuel. It works with kilometers or miles, liters or gallons, and every common fuel-economy unit, so you can use the figures on your dashboard and at your local pump — even when traveling abroad.

Features

  • Kilometers or miles.
  • Four fuel-economy units: L/100 km, km/L, US mpg and UK mpg.
  • Price per liter, US gallon or UK gallon.
  • Round-trip option and cost per person for carpooling.
  • Cost per kilometer or mile to compare cars and routes.

Fuel economy conversions

L/100 km km/L US mpg UK mpg
4 25.0 58.8 70.6
5 20.0 47.0 56.5
6 16.7 39.2 47.1
7 14.3 33.6 40.4
8 12.5 29.4 35.3
10 10.0 23.5 28.2
12 8.3 19.6 23.5

Saving fuel

  • Drive smoothly: gentle acceleration and anticipating stops can save 10–20%.
  • Slow down: fuel use rises sharply above about 90 km/h (55 mph).
  • Check tire pressure monthly — under-inflated tires increase consumption.
  • Lighten the load and remove roof boxes when you don't need them.

Related tools

Convert pump volumes with liters to gallons, distances with km to miles, or fuel prices abroad with the Currency Converter.

Frequently asked questions

How is the fuel cost calculated?
Fuel needed = distance × consumption, and cost = fuel needed × price. For 300 km at 7 L/100 km: 300 × 7 ÷ 100 = 21 liters; at 1.80 per liter that costs 37.80.
How do I convert mpg to L/100 km?
Divide 235.21 by US mpg (or 282.48 by UK mpg). 30 mpg (US) = 7.84 L/100 km. The calculator converts automatically, so you can mix units — for example US mpg with a price per liter.
Where do I find my car's fuel economy?
Most cars show average consumption on the dashboard or trip computer. Otherwise, check the manufacturer's figures, but expect real-world consumption to be 10–25% higher, especially in city traffic, cold weather or at high speed.
Why are US and UK gallons different?
A UK (imperial) gallon is 4.546 liters, while a US gallon is 3.785 liters. That's why a car's mpg figure is about 20% higher in UK mpg than in US mpg.
Does it include tolls, parking or wear?
No — only fuel. For a full trip budget, add tolls, parking, and if you want to be thorough, an allowance for tires, servicing and depreciation.

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