Fuel Economy Converter
Convert fuel economy between MPG, L/100km and km/L.
Results update as you type.
About this calculator
A fuel economy converter translates a vehicle efficiency figure between US and UK miles per gallon, liters per 100 km, and kilometers per liter. Because L/100km is inverse to the mpg and km/L measures, the tool converts through L/100km rather than a simple multiplier.
Frequently asked questions
How do I convert MPG to L/100km?
They are inversely related: L/100km = 235.215 ÷ MPG (US). So 30 US mpg is about 7.84 L/100km. A higher mpg but a lower L/100km both mean better economy.
Why are US and UK MPG different?
A UK gallon is about 20% larger than a US gallon, so the same car scores higher mpg in UK figures. Always note which gallon a quoted mpg uses.
What is km/L?
Kilometers per liter is used in parts of Asia and is proportional to mpg. Convert via L/100km = 100 ÷ (km/L).
Results are estimates for general guidance only, not financial, medical or tax advice.