Fuel Economy Unit Converter
Local ProcessingConvert vehicle fuel economy ratings between km/L, US MPG, UK MPG, and L/100km.
How It Works & Processing Standards
Enter values above to calculate results automatically. Check each input field for guidance and units.
Example: Efficiency Rating = 10, Source Unit = km/L, Target Unit = L/100km → 10
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Fuel economy units point in different directions: km/L and mpg are better when higher, L/100km when lower. The conversion accounts for that.
1 US mpg = 0.425143707430272 km/L and 1 UK mpg = 0.354006189934647 km/L (fixed by the spec).
How to Use Fuel Economy Unit Converter
- 1Enter the valueIt must be greater than 0.
- 2Choose unitsPick the unit you have and the unit you want.
- 3Read the resultThe converted figure appears immediately.
Examples
Common Use Cases
- Reading US spec sheets in km/L
- Comparing European L/100km figures
- Seeing the gap between US and UK mpg
Frequently Asked Questions (FAQ)
Why is L/100km inverted?
It is fuel used per 100 km, so better economy means a smaller number. The conversion uses the reciprocal, not a multiplier.
Why do US and UK mpg differ?
A UK gallon (about 4.546 L) is larger than a US gallon (about 3.785 L), so the same car shows a higher UK mpg.