Fuel Economy Calculator

Miles per gallon and trip cost.

Enter your values in the interactive calculator to see an instant result. Calculations run in your browser, without an account.

Results are estimates for educational use; confirm important decisions with appropriate experts.

Formula • Worked example • Interpretation

Estimate miles per gallon and trip fuel cost

Fuel economy relates a vehicle’s distance driven to fuel consumed. Trip-cost estimates use an assumed price per unit of fuel.

Miles per gallon (MPG) = miles traveled ÷ gallons used. Fuel cost = gallons used × price per gallon.

Driving 300 miles with 10 gallons gives 30 MPG. At $3.50 per gallon, the fuel used costs $35.

Higher MPG means less fuel used for the same trip length. Actual results depend on traffic, speed, weather and driving conditions.

For a reliable personal MPG measurement, compare miles and gallons across several complete refueling cycles.

Electric vehicle energy consumption is measured differently (for example kWh per 100 miles). Fuel price and mileage can change during a trip.

SiCalcs tools provide estimates and educational calculations; they do not replace professional financial, medical, tax, or legal advice.