All major fuel economy units
Converts between mpg (US and UK), L/100km, km/L, and mi/L — covering standards used across North America, Europe, Asia, and Australia.
Fuel Economy & Gas Mileage Calculator
Convert fuel economy between L/100 km, km/L, and MPG, compute real-world gas mileage from odometer logs, and calculate total trip fuel costs accurately.
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How to use Fuel Economy & Gas Mileage Calculator
- 1
Enter a fuel economy value in your current unit.
- 2
Select the input unit (mpg, L/100km, km/L, or mi/L).
- 3
Read the automatic conversion into all other fuel economy units.
Why use this tool?
US and UK gallon distinction
Correctly distinguishes between the US gallon (3.785 L) and the Imperial gallon (4.546 L) to avoid the common mpg comparison error.
Instant multi-unit display
Shows all conversions simultaneously so you can compare your vehicle's efficiency with any international specification.
Frequently asked questions
How do I convert L/100km to mpg?
To convert L/100km to US mpg: divide 235.21 by the L/100km value. For example, 8 L/100km = 235.21 ÷ 8 = 29.4 mpg (US). Note that UK mpg uses a different gallon — use the converter for accurate results.
What is a good fuel economy for a car?
In the US, 30+ mpg is considered good fuel economy for a non-hybrid car. In metric terms, that is approximately 7.8 L/100km or better. Hybrid vehicles typically achieve 50+ mpg (under 4.7 L/100km).
Can I convert between US MPG, UK MPG, and L/100km?
Yes. The converter easily converts between US Miles per Gallon, Imperial (UK) MPG, and European Liters per 100 Kilometers.
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