Fuel Economy Converter
Convert between MPG (US/UK), km/L and L/100km — including the inverse L/100km scale.
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Step by step
The formula
normalise to km/L, then to target; L/100km = 100 ÷ (km/L)
Two philosophies collide here. MPG and km/L measure distance per fuel, so higher is better. L/100km measures fuel per distance, so lower is better. Converting between them means inverting, which is why the numbers move in opposite directions.
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Example calculations
Common questions this calculator answers — select one to load its values.
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Frequently asked questions
Why is L/100km “backwards”?+
Lower L/100km means better economy, because it measures fuel used per distance — the inverse of mpg or km/L, where higher is better.
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