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Gas Mileage Calculator (MPG)

Calculate fuel economy in MPG, km/L, and L/100km. Optional cost-per-mile if you enter the price per gallon.

Trip details

Fuel economy

30 MPG

km / liter

12.75

L / 100 km

7.84

Trip cost

$35.00

Cost per mile

$0.1167

Frequently Asked Questions about the Gas Mileage Calculator (MPG)

How do I calculate MPG?
Divide the miles you drove by the gallons of fuel used. 300 miles / 10 gallons = 30 MPG.
What is good gas mileage?
Average new US cars get 25-30 MPG combined. Hybrids 45-55 MPG. SUVs and trucks 18-25 MPG. EVs are typically rated in MPGe at 100+ equivalent.
How do I convert MPG to L/100km?
L/100km = 235.21 / MPG. So 30 MPG = 7.84 L/100km. The conversion is inverse because L/100km goes down as efficiency goes up.
Why is my real-world MPG lower than the EPA estimate?
EPA estimates use standardized lab tests. City driving, cold weather, AC use, and aggressive acceleration can all reduce real-world MPG by 10-25%.
How can I improve my gas mileage?
Smooth driving (avoid hard acceleration and braking), proper tire pressure, regular maintenance, lighter loads, and steady speeds. Easing off the gas above 60 MPH helps too.