Gas Mileage Calculator

Calculate fuel economy in MPG or L/100km from distance traveled and fuel used.

How Gas Mileage Is Calculated

Fuel economy measures how far a vehicle travels per unit of fuel. The two most common standards are miles per gallon (MPG), used in the United States, and liters per 100 kilometers (L/100km), used across most of the world. The formulas differ slightly:

  • US (MPG): Divide the distance in miles by the gallons of fuel used. A higher number means better efficiency.
  • Metric (L/100km): Divide liters of fuel by the distance in kilometers, then multiply by 100. A lower number means better efficiency.

Tips to Improve Your Fuel Economy

Smooth Driving

Gentle acceleration and braking, plus steady highway speeds, can significantly reduce fuel consumption compared to aggressive driving.

Tire Pressure

Underinflated tires increase rolling resistance. Keeping tires at the recommended pressure improves both safety and mileage.

Reduce Weight & Drag

Remove unnecessary cargo and roof racks when not in use. Extra weight and aerodynamic drag both lower fuel efficiency.

Note: This calculator is for informational purposes only. Real-world fuel economy varies with driving conditions, vehicle maintenance, terrain, and load. Use the results as a guide for tracking and comparison.