Fuel cost calculator
Cost of a journey from distance, fuel economy and fuel price.
How it works
Calculates what a trip costs in fuel, and the cost per person if you split it. Works in miles per gallon, litres per 100 km or kilometres per litre.
The three economy units are not interchangeable in the way people assume, because two of them are inverted relative to the third. Litres per 100 km is consumption — lower is better — while miles per gallon and km per litre are efficiency, where higher is better. This also means the same absolute change means different things: improving from 20 to 25 mpg saves far more fuel over the same distance than improving from 40 to 45.
US and imperial gallons differ by about 20%, so a figure quoted in mpg is meaningless without knowing which. This calculator asks.
This tool runs entirely in your browser. Nothing you enter is sent to a server, logged or stored, and the page keeps working with the network disconnected.
Common questions
- Is a US gallon the same as an imperial gallon?
- No. A US gallon is 3.785 litres and an imperial gallon 4.546, about 20% larger. The same car quotes noticeably higher mpg in imperial.
- Why does improving from 20 to 25 mpg save more than 40 to 45?
- Because mpg is inverted. Going 20 to 25 cuts consumption by a quarter; 40 to 45 cuts it by about a ninth.
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Sources
- Calculated on this page — At One Place