⛽ Fuel Economy Converter
Enter a value, choose the unit you have and the unit you want. All other common units are listed too.
Converted value
How the Fuel Economy Converter works
Each value is converted to a base unit using exact, internationally defined factors, then to the unit you want.
km/L = mpg(US) × 0.425144 · L/100 km = 235.215 ÷ mpg(US) · mpg(UK) = mpg(US) × 1.20095
Step-by-step calculation
- 1Enter the value.
- 2Choose the unit you have and want.
- 3Convert through km per liter.
Worked example
30 mpg (US) = 7.84 L/100 km = 12.75 km/L = 36.03 mpg (UK).
Fuel Economy Converter examples
| Value | Converted value |
|---|---|
| 15 | 15.68 L/100 km |
| 23 | 10.23 L/100 km |
| 30 | 7.84 L/100 km |
| 38 | 6.19 L/100 km |
| 45 | 5.23 L/100 km |
Other inputs kept at the calculator's default values. Results calculated by this calculator.
Why use a Fuel Economy Converter?
Compare car fuel economy between countries.
Important factors that can affect your results
- US vs UK gallons.
- L/100 km: lower is better.
- Real-world driving differs from ratings.
Frequently asked questions
Why is L/100 km "backwards"?
It measures fuel used per distance, so lower is better, while mpg measures distance per fuel, so higher is better.
Why do UK and US mpg differ?
Because a UK gallon is larger than a US gallon.
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Last reviewed November 2026 · How we build and check our tools · Report a problem