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Fuel Economy in US/UK MPG & L/100 km

10 km/L equals 10 L/100 km. US MPG and UK MPG differ because their gallons differ. Select compatible units to convert or solve from an entered equivalent quantity.

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Calculator inputs

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How to use this calculator

  1. Enter the known values in the units shown. Results update as you type.
  2. Where results are editable, change one to solve backwards. Lock a value to hold it fixed.
  3. Use the worked example to check the method. Reset restores the starting fields.

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Formula and method

10 km/L equals 10 L/100 km. US MPG and UK MPG differ because their gallons differ.

L/100 km = 100 / (km/L); MPG uses the specified US or Imperial gallon.

Worked example

Enter these known values and leave the other values blank.

Kilometers per liter
10 km/L
Miles per US gallon
23.52 US mpg
Miles per UK gallon
28.25 UK mpg
Liters per 100 kilometers
10 L/100 km

Assumptions and limitations

  • Arithmetic uses 64 significant decimal digits. Displayed values are rounded separately.
  • Each field represents the same quantity in its selected units; enter one known value to calculate its equivalents.
  • The finite reciprocal model requires positive fuel consumption/economy. Zero fuel use has an unbounded distance-per-fuel reciprocal.
  • A US liquid gallon is 3.785411784 L; an Imperial gallon is 4.54609 L. An international mile is 1.609344 km.
  • Lower L/100 km indicates less fuel used per distance; higher MPG or km/L indicates more distance per fuel. Driving conditions are not predicted.

Common questions

Can I use the same MPG value for US and UK gallons?

Specify the gallon. The Imperial gallon contains more liters, so a numerical UK MPG differs from US MPG for the same vehicle economy.

References

US MPG uses the same exact US gallon as volume and price inputs.

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