How to convert Miles per US gallon to litres per 100 kilometres
L/100 km = 235.214583333333 ÷ mpg (US)
Divide 235.214583333333 by the positive mpg (US) reading. This is a reciprocal relationship: doubling mpg (US) halves L/100 km. The US liquid gallon is 3.785411784 liters. Zero and negative readings are not supported.
Worked examples
30 mpg (US) ≈ 7.840486111 L/100 km
235.214583333333 ÷ 30 ≈ 7.840486111
50 mpg (US) ≈ 4.704291667 L/100 km
235.214583333333 ÷ 50 ≈ 4.704291667
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.