Calculate Gas Mileage

Improve Gas Mileage through Knowledge

I found myself happy to explain how I calculate my gas mileage, MPG (miles per gallon), recently. Basically, I start by filling my tank and recording my odometer at the time of fill-up. Then, I drive around until the tank is below one quarter full. Then I fill my tank and record the odometer. Then I take how many gallons it took to fill it and divide it into the difference of the number of miles between odometer reads.

For example, the last time I filled my car with gas the odometer read 189 miles. It took 8 gallons to fill the tank. My odometer at the time of the fill read 429. 429 - 189 = 240 miles. 240 miles on 8 gallons is 30 miles per gallon.

I have a 2006 Chevy Aveo. The Aveo is supposed to be good on gas usage. I will be recording my gas mileage in the chart below. Does your Chevy Aveo do better?

I have added average temperature to the chart as suggested by a thinker of things. This hypermiler is also a source of inspiration. Thanks!

Roll your own!

• Enter how many gallons it took to fill your tank in Gallons-to-Fill.
• Enter how many miles you drove since your last fill.
• Enter how much you most recently paid for gas.
• Click the 'Roll Your Own' button.

Tip A: Avoid Rush Hour Traffic! Look how much my mileage dropped! I went from over 30 to just over 26 when snow hit Cleveland for the first time this season. The first snowfall seems to throw everyone into slow driving mode. What was usually a 45 minute commute became a 2 hour and 45 minute commute! This totally shot my mileage for that tank. Remember, when your mileage is lower, and your gas cost per mile is higher, it badly affects both equations.

Tip B: Watch those RPM's! I purposely watched my driving style and kept my RPM's under 3000, even when accelerating. Rapid Acceleration wastes gas. Slower, steadier speed-ups will keep the money in your wallet instead of emitting out your exhaust! Remember, if you are going to go fast or speed up, take a slower acceleration rate to get there.

Tip C: From Papa John: Regular oil changes will help your gas mileage as friction is reduced with cleaner oil. Cold Weather can cause the air pressure in your tires to drop 10 or more pounds. When the outside air temperature drops below 32 degrees the air pressure in your tire drops and a return to 70 degree weather WILL NOT cause an increase. Anytime that you walk up to your vehicle is the best time to inspect your tires. A low pressure tire can be seen, if you look for it. Purchase a decent tire pressure gauge, keep it in the glove compartment and use it, do not depend on the reading you get at the air pump. I keep my tires at 35 pounds , 32 is a widely recommended pressure. Maintaining tire air pressure will extend the life of your tire.

Explanations of calculations:

• Odometer: The reading on the odometer at the time of fill-up.
• Gallons-to-Fill: How many gallons of gas it took to refill the tank.
• Miles Since Last Fill: The subtraction of the odometer readings since the last fill.
• Miles per Gallon: The number of Miles Since Last Fill divided by the Gallons-to-Fill.
• Cost of gas: The amount paid per gallon at the time of the fill.
• Vendor - Pump #: The vendor of the gas and the pump number used.
• Gas Cost Per Mile: Gallons-to-Fill multiplied by Cost of gas, and then divided by Miles Since Last Fill.
• Drive Style: This is my own judgement call. Non-Aggressive: Just below speed limit. Semi-Aggressive: Just above speed limit. Aggressive: 5 to 10 miles over the speed limit for longer periods of time.
• Drive Times: Because most of the miles are highway miles, the Drive Times affects the stop and go amount.

It is my hope that this page helps you figure out your miles per gallon. With good mileage, you can save money. If you have any questions about improving fuel efficiency, just mail me through the 'mail' link above and I will try to help out!