Fuel Economy Converters
Convert between MPG, L/100km, and km/L (US and imperial).
Fuel economy describes how far a vehicle travels per unit of fuel, or how much fuel it uses per distance. The US uses miles per gallon (MPG), where higher is better. Most of the world uses liters per 100 kilometers (L/100km), where lower is better. Because one measures distance-per-fuel and the other fuel-per-distance, converting between them is an inverse relationship — you divide a constant (about 235.2 for US gallons) by the value, not multiply. US and imperial gallons are also different sizes, so US MPG and UK MPG are not the same number.
Reviewed August 2026
4 Converters
Featured Guides
MPG Explained
What miles per gallon really tells you about fuel use.
L/100km Explained
The fuel-per-distance measure used in Europe and why lower is better.
Why MPG and L/100km Convert Differently
The inverse relationship that means you divide, not multiply.
US MPG vs Imperial MPG
Why the same car gets different MPG numbers in the US and UK.