Fuel economy converter
What is a Fuel Economy Converter?
Fuel economy is expressed in different ways around the world. The US uses miles per US gallon, the UK uses miles per imperial gallon, much of Asia uses kilometres per litre, and Europe and Australia use litres per 100 kilometres. This converter translates between them so you can compare vehicles fairly.
How to use it
- Enter a value and choose its unit.
- Read the equivalent in all other units.
Conversion factors
L/100km = 235.215 / US MPGL/100km = 282.481 / UK MPGkm/L = 100 / (L/100km)- 1 UK MPG = 0.8327 US MPG, because an imperial gallon (4.546 L) is larger than a US gallon (3.785 L).
Examples
- 30 US MPG = 7.84 L/100km = 12.75 km/L = 36.0 UK MPG.
- 5.0 L/100km = 47.0 US MPG = 56.5 UK MPG = 20 km/L.
Why L/100km is easier to reason about
MPG and km/L are distance per fuel, so improvements are not linear in fuel saved. Going from 10 to 20 MPG saves far more fuel than going from 40 to 50 MPG. Over 1,000 miles, the first change saves 50 gallons, while the second saves only 5. L/100km measures fuel per distance, so savings are proportional and comparisons are intuitive.
Estimating trip cost
Fuel needed = distance × L/100km / 100. A 450 km trip at 6.5 L/100km uses 29.25 litres; at 1.80 per litre that is about 52.65.
Frequently Asked Questions
How do I convert MPG to L/100km?
Divide 235.215 by the US MPG value, or 282.481 by the UK MPG value.
Why are UK and US MPG different?
An imperial gallon is about 4.546 litres, while a US gallon is about 3.785 litres.
Is a higher L/100km better?
No. L/100km measures fuel used, so lower values mean better economy.
How do I estimate fuel for a trip?
Multiply the distance in kilometres by the L/100km figure and divide by 100.