Fuel Economy Unit Converter
Convert between US MPG, UK MPG, L/100km and km/L instantly. Free fuel economy converter.
A US gallon is 3.785 L, a UK gallon is 4.546 L - so the same car scores 20% higher in UK MPG.
Frequently asked questions
- What is the difference between US and UK MPG?
- The gallon. A US gallon is 3.785 litres and a UK gallon is 4.546, so UK MPG numbers are about 20% higher for the same car.
- How do I convert MPG to L/100km?
- Divide 235.215 by the US MPG figure. The constant comes from the gallon-to-litre and mile-to-km conversions.
- What is good fuel economy?
- About 5 L/100km (47 US MPG) is efficient for a gasoline car. Pickup trucks often sit near 13 L/100km (18 MPG).
- Which figure do European labels use?
- L/100km, where lower is better. The US and UK use MPG, where higher is better.
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