Fuel economy calculator
Measure fuel consumption from a trip distance and refill quantity.
Formula
L/100 km = liters × 100 / kilometers; mpg = miles / US gallons
Distance traveled: 300 mi · Fuel used: 10 US gal · Fuel consumption ≈ 100000×(10 US gal × 3.785411784 L/US gal)÷(300 mi × 1,609.344 m/mi) · US fuel economy ≈ (300 mi × 1,609.344 m/mi)÷1609.344÷((10 US gal × 3.785411784 L/US gal)÷3.785411784) · Distance per liter ≈ (300 mi × 1,609.344 m/mi)÷1000÷(10 US gal × 3.785411784 L/US gal)
How to use
- Enter the distance traveled.
- Enter the fuel used and its gallon or liter type.
- Read consumption and fuel economy.
Examples
- 500 km using 40 L gives 8 L/100 km and 12.5 km/L.
Frequently asked questions
How should I measure fuel used?
Compare two consistent full-tank refills and the distance driven between them.
Which gallon does mpg use?
The output is US mpg; UK gallons can be selected separately for fuel input.
Is lower always better?
Lower L/100 km is better; higher mpg or km/L is better.
Sources
Updated: