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Automotive units

Fuel Efficiency Converter

Convert between MPG, L/100 km and km/L without treating one regional unit as universal.

Why the units feel reversed

MPG and km/L get better as the number gets higher. L/100 km gets better as the number gets lower because it measures fuel consumed for a fixed distance.

Example

35 MPG US is about 6.72 L/100 km. The same value is also about 14.88 km/L.

Common mistakes

Do not mix US MPG and Imperial MPG. The gallons are different, so the same numeric MPG value converts to different metric results.

Limitations

This converter handles units only. Real-world efficiency changes with driving style, speed, temperature, load, tires, terrain and test cycle.

Last reviewed: 2026-05-17

Before relying on this result

Use this calculator together with the formula, assumptions, limitations and examples on the page. If the topic involves health, tax, lending, investment, legal, safety or current-rate decisions, treat the number as an estimate and check the relevant primary source or professional guidance.

Calculator metadata last reviewed: 2026-05-14.