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 Whats Your MPG! Do you know how much your spending on gas? Miles Per Gallon can be calculated in these four easy to follow steps...
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 60 MPG 2006 Toyota Prius

Calculating MPG
MPG can be calculated in four easy steps:

Step 1. Filling the vehicle's gas tank completely and writing down the vehicle's odometer reading (mileage).

Example: The last time the tank was filled, the odometer reading was 32,645.1 miles.

Step 2. When it's time to refuel, filling the tank completely and writing down the number of gallons it took to fill the tank and the vehicle's new odometer reading. Once two odometer readings are taken, MPG can be calculated.

Example: The next time the tank was filled, the odometer reading was 33,001.3. It took 13.5 gallons to fill the tank.

Step 3.
Calculating the distance driven by subtracting the previous odometer reading from the new one.

Example: The distance driven would be 33,001.3 minus 32,645.1, or 356.2 miles.

Step 4. Dividing the number of miles driven by the number of gallons it took to fill the tank. The result is the vehicle's MPG for that driving period.

Example: 356.2 miles divided by 13.5 gallons equals 26.4 miles per gallon.

The MPG for that driving period would be 26.4.

Alternate Method

If you use your vehicle's trip odometer, MPG can be calculated by

Step 1. Filling the vehicle's gas tank completely and re-setting the trip odometer.

Note: Sometimes it's easy to get the main odometer and trip odometer readings confused, especially if the vehicle is new.

Step 2.
When it's time to re-fuel
Filling the tank completely
Writing down the number of gallons it took to fill the tank
Writing down the mileage on the trip odometer
Re-setting the trip odometer
Example: It took 9.5 gallons to completely fill the tank, and the trip odometer reads 335 miles.

Step 3. Dividing the number of miles driven by the number of gallons it took to fill the tank. The result is the vehicle's MPG for that driving period.

Example: 335 miles divided by 9.5 gallons equals 35.5 miles per gallon.