What Is the Mileage Calculator?
This mileage calculator measures your vehicle's fuel economy in miles per gallon (MPG), the most common efficiency metric used in the United States. By dividing the distance you traveled by the amount of fuel you burned, it tells you exactly how far your vehicle goes on each gallon — a handy way to track efficiency, budget for fuel, or compare cars.
How to Use It
Fill up your tank completely and reset your trip odometer. Drive normally until you need to refuel, then fill up again and note how many gallons it took. Enter the miles shown on your trip odometer and the gallons added at the second fill-up. The calculator returns your MPG along with gallons used per 100 miles.
The Formula Explained
The core formula is simply:
$$\text{MPG} = \frac{\text{Miles Driven}}{\text{Gallons Used}}$$
A higher MPG means better efficiency. The secondary figure, gallons per 100 miles, is calculated as $$(\text{Gallons} \div \text{Miles}) \times 100$$ and is useful for estimating fuel needs on long trips.
Worked Example
Suppose you drove 300 miles and used 12 gallons of gasoline. Your fuel economy is $$300 \div 12 = 25 \text{ MPG}$$ The gallons per 100 miles is $$(12 \div 300) \times 100 = 4 \text{ gallons}$$ So on a 400-mile trip you'd expect to use roughly 16 gallons.
FAQ
What's a good MPG? Most modern gasoline cars achieve 25–35 MPG combined; hybrids often exceed 50 MPG.
Does driving style affect MPG? Yes. Hard acceleration, high speeds, idling, and underinflated tires all lower fuel economy.
Can I use this for kilometers and liters? This tool uses US miles and gallons. For metric efficiency (L/100km) use those units instead.
