How to convert Miles per Imperial gallon to litres per 100 kilometres
L/100 km = 282.480936331822 ÷ mpg (UK)
Divide 282.480936331822 by the positive mpg (UK) reading. This is a reciprocal relationship: doubling mpg (UK) halves L/100 km. The Imperial gallon is 4.54609 liters. Zero and negative readings are not supported.
Worked examples
30 mpg (UK) ≈ 9.416031211 L/100 km
282.480936331822 ÷ 30 ≈ 9.416031211
50 mpg (UK) ≈ 5.649618727 L/100 km
282.480936331822 ÷ 50 ≈ 5.649618727
Frequently asked questions
Why does the numerical direction reverse?
Consumption measures fuel used per distance; economy measures distance per fuel volume. They are reciprocals. A lower L/100 km reading corresponds to a higher km/L or mpg reading. This tool requires positive finite inputs.