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Fuel Economy Converter

Fuel Economy Converter

Convert between mpg (US), L/100km, and km/L.

Results update as you type.

How to use

Enter a fuel economy value and choose whether it is mpg, L/100 km, or km/L. Read the converted values.

Formula

L/100 km = 235.214583 ÷ mpg (US)
km/L = 100 ÷ (L/100 km)
mpg = 235.214583 ÷ (L/100 km)

Worked example

  1. 25 mpg (US) → about 9.41 L/100 km.

Assumptions

  • US gallons are used for mpg (not imperial gallons).
  • Conversion factors are fixed; they do not vary by fuel type.

FAQs

Is this US or UK mpg?
US gallons. UK (imperial) mpg numbers are higher for the same car.
How do I go from L/100 km to mpg?
mpg ≈ 235.21 ÷ (L/100 km). Enter L/100 km and read the mpg result.
Why do sticker ratings disagree with my tank math?
Sticker figures are lab cycles. Your mix of city, highway, and weather will differ.
Can I use this before a fuel cost estimate?
Yes. Convert to mpg or km/L, then open the Fuel Cost calculator.