How it's calculated
MPG = miles ÷ gallons
miles = distance driven, gallons = fuel used. L/100km = 235.215 ÷ MPG; cost per mile = gas price ÷ MPG.
Common questions
How do I calculate MPG?
Divide the miles you drove by the gallons of fuel you used. 300 miles on 10 gallons is 30 MPG.
Why is UK MPG higher than US MPG?
The Imperial gallon is about 20% larger than the US gallon, so the same car shows a higher MPG figure in the UK.