Gas Mileage Calculator

Calculate gas mileage, MPG, fuel used, trip fuel cost, cost per mile, and estimated range per tank. Use this gas mileage calculator to estimate your vehicle fuel economy and driving costs.

Calculate Gas Mileage

MPG = Miles Driven ÷ Gallons Used. Trip Cost = Trip Distance ÷ MPG × Fuel Price.
Your result will appear here.

How the gas mileage calculator works

MPG from miles and gallons:
Enter miles driven and gallons used to calculate your vehicle gas mileage.

Fuel needed for trip:
Enter trip distance and vehicle MPG to estimate how many gallons of gas are needed.

Trip fuel cost:
Enter trip distance, MPG, and fuel price to estimate your total fuel cost.

Range per tank:
Enter tank size and MPG to estimate how far you can drive on a full tank.

Why use a gas mileage calculator?

A gas mileage calculator helps estimate vehicle fuel economy, trip costs, annual fuel costs, and how far you can drive before refueling.

It can help compare vehicles, plan road trips, track fuel spending, and understand how driving habits affect fuel use.

What your result means

Your result shows MPG, gallons needed, trip fuel cost, cost per mile, range per tank, annual fuel used, and annual fuel cost. These are estimates based on the numbers you enter. Actual fuel economy can change based on traffic, speed, tire pressure, cargo weight, weather, maintenance, and driving style.

Gas mileage calculator formulas

Frequently asked questions

What is gas mileage?

Gas mileage is a measure of how far a vehicle can travel using a certain amount of fuel. In the United States, it is commonly shown as miles per gallon, or MPG.

How do you calculate MPG?

Divide the number of miles driven by the number of gallons of fuel used.

How do you calculate fuel cost for a trip?

Divide the trip distance by your vehicle MPG to estimate gallons needed, then multiply by the fuel price per gallon.

Why does my gas mileage change?

Gas mileage can change because of speed, traffic, weather, tire pressure, vehicle maintenance, cargo weight, terrain, and driving habits.