Fuel Efficiency Converter
Convert fuel efficiency between km/L, L/100km, MPG (US), MPG (UK). Compare fuel economy across units.
About this calculator
Compare cars across countries with one tool. Enter a fuel efficiency in km/L, L/100 km, MPG (US) or MPG (UK) and convert it to another of the four units.
Fuel efficiency in L/100 km moves the opposite way to km/L: a car that does 20 km/L uses 5 L per 100 km, and one that does 10 km/L uses 10 L per 100 km.
How to use it
- Type the Value.
- Choose the From and To units.
- Press Convert.
Method
Converted via km/L: MPG (US) = km/L × 2.352146, MPG (UK) = km/L × 2.824809 and L/100 km = 100 ÷ km/L.
Worked example
Examples
| 15 km/L | 6.6667 L/100 km |
| 30 MPG (US) | 12.7543 km/L |
| 30 MPG (UK) | 10.6202 km/L |
| 8 L/100 km | 12.5 km/L |
Tips and common mistakes
- Use the same unit when comparing cars.
- Hybrids and EVs are often quoted in L/100 km equivalents.
- Driving style affects mileage by 20% or more.
- Remember that US and UK gallons differ.
- Use trip meters to measure real mileage by filling the tank to the brim each time.
Frequently asked questions
How do I convert km/L to MPG?
Multiply by 2.352 for US MPG.
What is L/100 km?
Litres of fuel needed for 100 km of driving.
Which is better, 6 L/100 km or 15 km/L?
15 km/L is 6.67 L/100 km, so 6 L/100 km is better.
Why is UK MPG higher?
Because the UK gallon is larger.
How can I improve mileage?
Smooth driving, correct tyre pressure and regular servicing.
Is a lower L/100 km better?
Yes.