fd648e4638ef356bcb25d96a30673feb

The ABCs of MPG: How to Calculate Gas Prices for Your Road Trip

As COVID-19 vaccinations continue to increase, so is travel. In fact, 60 percent of Americans say they are planning to travel for leisure in the next several months.

If you are among these, you may be mapping out a road trip with friends or family. And you are probably wondering the best way to calculate gas mileage so you can budget for fuel costs. 

Fortunately, there’s an easy and accurate way to do this. The information below lays out the steps and includes some factors to consider so you can make the most accurate determination. 

Calculate Gas Mileage

You likely have an idea of what kind of miles per gallon (MPG) your car gets. You may remember it advertised at the dealership or you looked it up online. But factors like terrain, the age of your car, and your driving style will impact this average. 

Expert Auto Repair Tip: Take it from someone who knows...Having the online repair manual is a life-saver when it comes to DIY auto repair and maintenance. Whether you are working on a Ford, BMW, Dodge, or something more exotic; we probably have the manual you need.

Find Your Online Car Repair Manual Today! ->>


There is a simple way to get a more accurate MPG estimate. The next time you fill up your car, jot down the odometer reading. Then drive normally until it is time to fuel up again.

Check the odometer again to determine how many miles you have driven. Then divide that by the number of gallons you put in your vehicle on the second fill-up.

This will give you the actual MPG for that particular trip. For an even more accurate reading, do this several times and average the outcomes.

Estimate Trip Distance

Use online route planners to calculate the distance you think you’ll travel on your trip. Remember to get total mileage that includes detours. If you’re uncertain about your itinerary, do your best to get a liberal estimate of how far you might go.

Once you have total mileage, divide that number by your vehicle’s MPG. This will give you the total gallons you will need for the trip.

To get gas prices, go to AAA’s site that lists the current average fuel price in the United States. Multiply that number by the gallons you think you’ll use.

Or, for a more accurate reading, look at the states where you will be traveling and average those two numbers together. You could also go with the higher numbers if you want to get the most you could possibly pay for fuel.

Other Variables

Note that terrain will impact fuel efficiency as well. More mountainous terrain will cost you more than open, flat plains. If you live in a major city and spent a lot of time sitting in traffic when calculating your MPG, you can expect to use less fuel if your trip is mostly long, open stretches of highways or interstates.

Sophisticated technologies like those used in a commercial fleet fuel management system can help you account for these factors. But they are probably not necessary for vacation-planning purposes.

Get Ready to Hit the Road

Now that you have any idea of how to calculate gas mileage and what factors will impact fuel costs, you can start planning. Using the simple steps above will let you know what you can expect to spend on your trip.

We hope these road trip tips are helpful to you. Be sure to check out our many other automotive posts, including those on travel, as well as car and motorcycle repair.