Conversions

Fuel Economy Converter

Convert vehicle fuel economy between miles per gallon (U.S.) and liters per 100 kilometers.

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Fuel Economy Converter

Enable JavaScript to use the interactive calculator; the example and formula are described below.

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How to use this fuel economy converter

Enter the requested values above and select Calculate. The result updates immediately on the page, so you can change one value and compare different scenarios without leaving the calculator.

Formula and method

L/100 km = 235.214583 ÷ MPG (US), and MPG (US) = 235.214583 ÷ L/100 km.

Example

30 mpg (U.S.) is about 7.84 L/100 km.

What this calculator is useful for

Convert vehicle fuel economy between miles per gallon (U.S.) and liters per 100 kilometers. It is designed for quick estimates and everyday problem solving. When a calculation affects a contract, tax filing, medical decision or other high-stakes situation, verify the result with the appropriate professional or authoritative source.

Why MPG and L/100 km move in opposite directions

Miles per gallon measures distance traveled for a fixed amount of fuel, so a higher MPG value indicates better fuel economy. Liters per 100 kilometers measures fuel used for a fixed distance, so a lower L/100 km value indicates better fuel economy. Because the two measures are reciprocals, they are converted by dividing the same constant by the input value.

L/100 km = 235.214583 ÷ MPG (U.S.)
MPG (U.S.) = 235.214583 ÷ L/100 km

Fuel economy examples

30 MPG (U.S.) is approximately 7.84 L/100 km. A vehicle rated at 8.0 L/100 km is approximately 29.40 MPG (U.S.). Actual fuel consumption can differ because of speed, temperature, terrain, vehicle load, tire pressure and driving conditions.

Fuel Economy Converter: a practical example

30 U.S. miles per gallon converts to about 7.84 liters per 100 kilometers; fuel use moves inversely with MPG.

What the result means

Smaller L/100 km numbers mean better efficiency, whereas larger MPG numbers mean better efficiency.

Limits to consider

This uses U.S. gallons, not imperial gallons, and assumes consistent fuel-economy test conditions.

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Frequently asked questions

What does the Fuel Economy Converter calculate?

Convert vehicle fuel economy between miles per gallon (U.S.) and liters per 100 kilometers.

How does the calculation work?

L/100 km = 235.214583 ÷ MPG (US), and MPG (US) = 235.214583 ÷ L/100 km.

Is this calculator free?

Yes. ERICH Calculators is free to use and no account is required.

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