Calculators
Gas Mileage Calculator
Calculate your vehicle's fuel economy.
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About the Gas Mileage Calculator
Find your real-world fuel economy. Enter the miles you drove and the gallons it took to refill and the calculator returns your mpg and the metric equivalent (L/100 km). Track it over a few tanks to spot maintenance issues or compare vehicles.
How to use the Gas Mileage Calculator
- 01Enter your miles driven and gallons used.
- 02Read the result instantly — it recalculates as you type.
- 03Adjust the numbers to model different scenarios.
Frequently asked questions
How do I calculate mpg?
Divide the miles driven by the gallons used to refill. Fill up, reset the trip meter, and refill to measure a tank accurately.
What is good gas mileage?
It varies by vehicle, but many modern cars get 25–35 mpg on the highway; hybrids can exceed 50 mpg.