MPG to L/100km Converter

MPG to L/100km Converter lets you switch between the two most common fuel economy standards.
Miles per gallon is used in the US, the UK, and a few other countries. Liters per 100 kilometers is used throughout Europe, Australia, and most of the world.

The formulas:

Converting MPG (US) to L/100km: L/100km = 235.215 ÷ MPG (US)

Converting MPG (UK/Imperial) to L/100km: L/100km = 282.481 ÷ MPG (UK)

Converting L/100km to MPG (US): MPG (US) = 235.215 ÷ L/100km

Why are there two MPG values (US and UK)? The US gallon (3.785 L) and the UK imperial gallon (4.546 L) are different sizes. A car rated at 40 MPG (UK) is NOT the same as 40 MPG (US). The UK number runs about 20% higher because the UK gallon holds more fuel, with nothing changed but the size of the container. Always check which standard a car’s rating uses, especially when a figure came off a British forum or magazine review.

Understanding the scales: Higher MPG = more efficient. Higher L/100km = less efficient. They work in opposite directions.

Reference values:

Ordered worst to best, so the two columns run in opposite directions down the table:

MPGe (miles per gallon equivalent) is the rating the EPA gives electric cars. It answers the question “how far would this car go on the energy in one gallon of gasoline”, which makes an EV comparable to a gas car on paper even though it never sees a gallon of anything.

Practical example: A European car rated at 6.5 L/100km converts to 235.215 ÷ 6.5 = 36.2 MPG (US), a reasonable economy car in US terms.

This converter works in both directions and handles both US and UK gallons. Fill in whichever box you have and leave the other blank. If you fill in both, the MPG box wins and the calculator says so.