Gas Mileage Calculator
Calculate fuel economy (MPG and L/100km) and running fuel costs from a trip's distance and fuel consumed.
Results
What is it?
Fuel economy measures how efficiently a vehicle converts fuel into distance traveled. MPG (miles per gallon) is used in the US, while L/100km is the standard in Canada, Europe, and Australia. Lower L/100km is better; higher MPG is better.
How to use
Fill up your tank, reset your trip odometer, drive normally, fill up again and record the distance and fuel used. Enter those values here along with the current fuel price to see your real-world economy — which is typically 10-20% lower than EPA-sticker estimates.
Example scenario
Driving 300 miles and using 10 gallons gives 30 MPG (7.8 L/100km). At $3.50/gallon, fuel costs $0.117/mile, or $11.67 per 100 miles. Over 15,000 miles per year, that's $1,750 in fuel annually.
Pro tip
The biggest hypermiling gains come from: (1) maintaining steady highway speed — wind resistance scales with speed squared, so 70 mph costs ~30% more than 60 mph; (2) avoiding jackrabbit starts; (3) proper tire inflation (+5% MPG per 10 psi under-inflation corrected). On long trips, draft behind large trucks at safe following distance to reduce aero drag by up to 20%.