## Best answer

The formula to calculate gas mileage:Miles driven gallons used to refill the tank. Take the miles traveled (from the trip computer), divide that by the number of gallons used to refill the tank. For example, the trip shows 200 miles since you last filled up, and it took 15 gallons to refill the tank.

## People also ask

### How do you calculate gas cost per mile?

If you supply price per gallon or price per liter, the gas calculator will also output gas cost per mile and miles per 1 USD, and if using the metric system the fuel cost will be in currency per kilometer (e.g. $ per km) and km per $. The formula to calculate mpg is: Gas mileagempg = (Current reading – Previous reading) / (Gas added to tank)

### Is it hard to figure out your gas mileage?

Fortunately, it doesn鈥檛 have to be difficult. You can use online gas mileage calculators or you can figure it out yourself using the calculator on your phone.

### Why use our simple gas trip calculator?

Our simple gas trip calculator can help you improve fuel economy, estimate mileage, and plan for a road trip! With fuel prices rising, it鈥檚 important to know what gas mileage you鈥檙e getting and at what cost.

### What is the MPG formula?

MPG formula. The formula to calculate mpg is: Gas mileage mpg = (Current reading – Previous reading) / (Gas added to tank) Calculating the cost per mile (or cost per kilometer), which is something our mpg calculator also does, is just a matter of a slight modification of the above formula: