Handle reciprocal fuel-consumption units correctly and keep US and Imperial gallons separate.
Trip fuel estimate
Method
Fuel economy formulas
Miles per gallon and kilometers per liter measure distance per fuel, while liters per 100 kilometers measures fuel per distance. Converting between them requires a reciprocal formula.
US and Imperial gallons are different sizes and remain separately labeled throughout the calculation.
Questions
Fuel Economy Converter FAQ
Why does a lower L/100 km value mean better economy?
Liters per 100 km measures fuel consumed for a fixed distance, so less fuel is better. MPG measures distance per fixed fuel, so higher is better.
Are US and Imperial MPG the same?
No. The Imperial gallon is larger, so the same vehicle has a numerically higher Imperial MPG value.
