How to Figure Miles Per Gallon of Gas

The more fuel efficient the car, the fewer gallons of gas you will use.

Miles per gallon, or mpg, measures how efficiently your car is using fuel in terms of the number of miles you drive. If your car does not have an instant mpg feature, you can find the average mpg each time you fill up with gas. If your gas efficiency is significantly different from the rate your car is expected to get, your car may need repairs or your driving habits may be costing you at the pump. Gas-wasting habits include rapid acceleration and braking, driving at speeds above 60 mph and idling.

Things You'll Need

• Calculator

Instructions

1. Reset your trip odometer the next time you fill up your car with gas. If your trip odometer does not work, or if your car does not have a trip odometer, you can still calculate your mpg by writing down your current odometer reading.

2. Note the number of miles driven the next time you fill up your car with gas by checking your trip odometer. If you noted the number of miles on your standard odometer, subtract that number from the current number to find the number of miles driven. For example, if your odometer was at 23,400 and now it reads 23,680, you would subtract 23,400 from 23,680 to find you drove 280 miles.

3. Divide the miles driven by the number of gallons you used to refuel your car to find the mpg of gas your car got. Finishing the example, if you had to put 16 gallons into your tank, you would divide 280 by 16 to find that you are getting 17.5 mpg.

References

• Department of Energy: Calculating Your MPG
• Department of Energy: Driving Sensibly