Free · Motion & time

Fuel Consumption & MPG Converter

Calculate fuel economy converter with editable inputs, reverse calculations, and unit choices.

  • Formula & worked example
  • Private in your browser
  • No signup
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Calculator inputs

Enter the values you know

Results update as you type. Edit a result to calculate another value, or lock a value to keep it fixed.

US mpg
UK mpg
L/100 km
km/L
Result

Your calculation

Enter enough known values to calculate the blanks.

How to use this calculator

  1. Enter the values you know in the units shown. Leave unknown values blank.
  2. Results update automatically as you type. Edit a result to calculate another value, or lock a value to keep it fixed.
  3. Reset restores the starting fields. A worked example appears below.

Private by default

Inputs and results stay in this browser tab. Bookify does not upload or store the values you enter.

Formula and method

Enter the values you know and leave unknown values blank. The equations below calculate the remaining values, including reverse calculations where enough inputs are available.

MPG = (100 × liters per gallon ÷ kilometers per mile) ÷ consumption in L/100 km

Worked example

Enter these known values and leave the other values blank.

Liters per 100 kilometers
8 L/100 km
Miles per US gallon
29.4 US mpg
Miles per UK gallon
35.31 UK mpg
Kilometers per liter
12.5 km/L

Assumptions and limitations

  • Inputs must satisfy the validation rules. Editing a result can recalculate an earlier input; lock values you want to keep fixed.

Common questions

Can I calculate a different unknown?

Yes. Clear that field and enter the other known values. The calculator uses the available inverse equations.

References

The calculation equations, inverse formulas, units, and input rules were imported from this source. Bookify provides the interface and equation solver.

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