Gas Mileage Calculator (MPG)

Divide the miles driven by the gallons of fuel used. Drive 300 miles on 10 gallons and you get 30 MPG. The calculator also shows km/L and L/100km, plus cost per mile and total cost if you enter the price per gallon.

New gas-powered cars in the US average around 25-30 MPG combined on the EPA cycle. Compact sedans often hit 35-40 MPG on the highway, while full-size trucks and large SUVs typically land in the 18-25 MPG range. Hybrids commonly reach 45-55 MPG, and EVs are rated in MPGe, usually 100 or higher.

Divide 235.21 by your MPG figure. At 30 MPG that gives you 7.84 L/100km. The relationship is inverse: as MPG goes up, L/100km goes down, so a higher L/100km number means worse fuel economy.

EPA ratings come from controlled lab cycles that do not fully capture stop-and-go city traffic, cold starts, air conditioning loads, roof racks, or hard acceleration. Real-world MPG often runs 10-25% below the label figure, and more in extreme conditions.

Keep tire pressure at the recommended PSI, accelerate and brake gradually, and ease off the gas on the highway, since fuel economy drops off rapidly above about 50 MPH. Removing unnecessary cargo, staying current on maintenance like the air filter and spark plugs, and using cruise control on long stretches each add a few MPG over time.