Fuel Cost Calculator - Free Online Tool

Estimate fuel needed and road-trip cost.

About this tool

Estimate fuel quantity and trip fuel cost from one-way distance, vehicle consumption or economy, and fuel price. Choose metric inputs (km, L/100 km, and price per litre) or US inputs (miles, US mpg, and price per US gallon), then optionally double the distance for a round trip.

How it works

  1. Select metric or US units and enter the one-way route distance in the displayed distance unit.
  2. Enter fuel consumption in L/100 km for metric, or fuel economy in US miles per US gallon for US units.
  3. Choose a currency and enter the local price per litre or US gallon in that currency, then choose one-way or round trip.
  4. Review the estimated total distance, fuel quantity, and cost.

Example use cases

  • Metric one-way trip: A 240 km trip at 7 L/100 km uses an estimated 16.8 L. At 1.70 currency units per litre, the estimated fuel cost is 28.56 currency units.
  • US round trip: A 150-mile one-way route at 30 US mpg becomes 300 miles for a round trip and uses an estimated 10 US gallons. Multiply by the price per US gallon for the trip estimate.

Frequently asked questions

Does the distance field take the full round-trip distance?

Enter the one-way distance. Selecting round trip doubles it; if you have already entered a round-trip total, leave the trip type as one-way to avoid doubling it again.

Are US mpg and imperial mpg interchangeable?

No. This calculator's US option uses US miles per US gallon. Use a matching US mpg figure and fuel price per US gallon; do not substitute imperial mpg without conversion.