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MPG or km-per-litre for a trip.
The Gas Mileage Calculator computes miles per gallon (mpg) from a trip's distance and the fuel it consumed. It also converts the result to km/L and litres per 100 km, and — if you enter a fuel price — estimates the total fuel cost of the trip and the cost per mile.
It is built around US units (miles and US gallons), making it ideal for tracking real-world fuel economy between fill-ups and for budgeting the fuel portion of a road trip.
Uses the US gallon (3.785412 L). L/100km and km/L are exact conversions of the mpg figure, not separate measurements.
Divide the miles you drove by the number of gallons used to refill the tank. For example, 300 miles on 12 gallons is 300 ÷ 12 = 25 mpg.
US gallons (3.785 litres). If you filled up in the UK or another country using Imperial gallons (4.546 L), your Imperial mpg will read higher for the same real economy.
Trip cost = gallons used × price per gallon. Cost per mile is that total divided by the miles driven, which is handy for comparing routes or vehicles.
It depends on the vehicle class. Small hatchbacks and hybrids often exceed 40 mpg, mid-size cars sit around 25–35 mpg, and large trucks or SUVs may be 15–20 mpg. Compare against your own past readings for a fair benchmark.