Fuel Calculator (MPG & L/100km)
Free online fuel-economy calculator. In US mode, enter gallons used, total fuel cost and miles driven to get MPG, cost per mile and cost per 100 miles; in metric mode it gives L/100km and cost per kilometre. Understand your real running cost — calculated locally. LifeRuns locally
Use this tool
How to use
- Choose US (miles/gallons) or Metric (km/litres).
- Enter the fuel used, its total cost and the distance driven.
- Fuel economy and cost metrics appear instantly.
Frequently asked questions
How is MPG calculated?
Miles driven ÷ gallons used gives miles per gallon, the standard fuel-economy figure in the US.
Why does it differ from my car's display?
The trip computer estimates; using actual fill-ups and distance (this tool) is closer to reality. Average across several fill-ups for the best picture.
Do I need both amount and volume?
Enter volume for economy and cost for the cost metrics; entering both gives every figure.