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Fuel Consumption Converter

Convert a fuel economy figure between US miles per gallon, UK (imperial) miles per gallon, liters per 100 kilometers and kilometers per liter. Enter one value and all four are shown together.

Quick examples
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Converted value7.84
US mpg
30 mpg
UK mpg
36.03 mpg
Liters per 100 km
7.84 L/100 km
Kilometers per liter
12.75 km/L

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      Formula

      L/100 km = 235.215 ÷ mpg (US)
      L/100 km = 282.481 ÷ mpg (UK)
      km/L = 100 ÷ (L/100 km)
      mpg (UK) = mpg (US) × 1.20095

      How to use it

      1. Enter the fuel economy figure.
      2. Choose the unit it is in.
      3. Choose the unit you want it in.
      4. Read the headline result, or use the full list below it.

      Worked examples

      30 US mpg in liters per 100 km

      Converted value
      7.84
      Liters per 100 km
      7.84 L/100 km
      UK mpg
      36.03 mpg
      Kilometers per liter
      12.75 km/L

      6 L/100 km in US mpg

      Converted value
      39.2
      US mpg
      39.2 mpg
      UK mpg
      47.08 mpg
      Kilometers per liter
      16.67 km/L

      50 UK mpg in US mpg

      Converted value
      41.63
      Liters per 100 km
      5.65 L/100 km

      Two kinds of scale

      Miles per gallon and km/L measure distance per unit of fuel, so higher is better. L/100 km measures fuel per unit of distance, so lower is better. Because one is the inverse of the other, equal steps in mpg are not equal fuel savings: going from 15 to 20 mpg saves more fuel over the same distance than going from 30 to 50 mpg.

      Quick reference

      20 US mpg = 11.76 L/100 km. 25 mpg = 9.41. 30 mpg = 7.84. 35 mpg = 6.72. 40 mpg = 5.88. 50 mpg = 4.70.

      A UK gallon is 4.546 liters against 3.785 for a US gallon, so UK mpg figures are about 20% higher for the same car. Check which one a review or advert is quoting before comparing.

      Questions people ask

      What is 30 mpg in L/100 km?

      7.84 L/100 km for US mpg (235.215 ÷ 30). For 30 UK mpg it is 9.42 L/100 km.

      What is 6 L/100 km in mpg?

      39.2 US mpg or 47.1 UK mpg.

      How do I convert km/L to mpg?

      Multiply km/L by 2.352 for US mpg or by 2.825 for UK mpg. 15 km/L is 35.3 US mpg.

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