Miles per gallons (MPG) refers to an average distance in miles a car travels using one gallon of gasoline. MPG is commonly used in the United States to characterise the fuel economy of a car. Other places such as Europe, Canada or China use the fuel consumption metrics that is an average number of litres of gasoline required to travel 100 kilometres. A higher litres per 100 kilometres value corresponds to a less fuel efficient car. Use a calculator to convert between fuel consumption and fuel economy values.

Divide 100 kilometres by the coefficient "1.609" to calculate miles: 100 divided by 1.609 equals 62.15 miles.

Divide litres by the coefficient "3.785" to convert them to gallons. For example, if the fuel economy is given as 13.5 litres /100 kilometres then 13.5 litres divided by 3.785 equals 3.567 gallons.

Divide 62.15 miles by the number of gallons to calculate MPG. In our example, 62.15 miles divided by 3.567 gallons equals 17.4 miles per gallon. Therefore, 13.5 litres per 100 kilometres is the same as 17.4 miles per gallon.