Gas Mileage Calculator
MPG from distance and gallons.
Inputs
mi
gal
Result
Mileage29.09 mpg
About the Gas Mileage Calculator
The Gas Mileage Calculator measures your car's real-world fuel economy from miles driven and gallons used between fill-ups.
Calculation method
MPG = Miles driven ÷ Gallons used.
MPG = Miles / GallonsHow to use this calculator
- Fill the tank and record the odometer.
- Drive normally, then fill again and record miles driven since the last fill.
- Enter miles and gallons to see actual MPG.
Example
300 miles driven on 10 gallons of fuel is 30 MPG.
Frequently asked questions
Why is my real MPG lower than the sticker?
EPA numbers use standardized cycles. Cold weather, short trips, aggressive driving, roof racks, and low tire pressure all reduce actual MPG by 10–25%.
How often should I check fuel economy?
Track a few tanks in a row for an accurate average. A sudden drop can signal maintenance issues — dirty air filter, bad O2 sensor, or dragging brakes.
Does premium fuel improve MPG?
Only for engines that specifically require premium. In cars tuned for regular, premium adds cost without meaningful MPG gains.
Disclaimer: This calculator is for informational and educational purposes only and does not constitute financial, tax, or legal advice. Consult a qualified professional for decisions specific to your situation.