How to calculate the gas cost of a trip

How to calculate gas cost for a trip


It’s easy to jump in the car and just drive, but when you’re taking a road trip, or even starting a new commute, a little planning goes a long way. Calculating the gas cost of a trip is a smart trick to budget travel expenses and can be completed in a few simple steps.


1. Calculate your miles per gallon

Fill up your gas tank and set the trip odometer button on the instrument panel to zero, then drive normally until it’s time to stop for gas again. When you next refuel, note the trip odometer reading to get the number of miles you’ve driven. Alternatively, you can get this figure by writing down the overall odometer reading the first time you fill up and again the second time, with the difference being your miles driven. Next, divide the mileage by the number of gallons of fuel you pumped on the second gas stop to get your miles per gallon.


2. Work out the trip distance

Whether you’re going point-to-point or taking a round trip, a quick look at resources such as Google Maps or your phone’s navigation app will tell how many miles the journey will be. This is a good time to select your preferred route, consider traffic hot spots to avoid and, if you’re planning a road trip, think about any sights and detours you want to build into the trip.


3. Get the price of gas

You may remember the price of gas from your last fill up but prices can fluctuate a lot over time and by region, so that may not be a good guide. Have a look at the current national and regional gas prices provided by the AAA to get an idea of what the price of gas will be for your journey.


4. Calculate the overall gas cost of your trip

 With miles per gallon, trip distance and the price of gas at your fingertips, you can calculate the gas cost of a trip with a simple formula. First, divide the distance of the trip by your miles per gallon figure to find out how many gallons of gas you will need. After that, multiply the number of gallons by the price of gas to calculate the gas cost for your journey. That’s it.


Other road trip expenses

Knowing how to calculate the gas cost of a trip is a useful way to plan ahead and, while it is more a guide than an exact figure, it will help you avoid an unexpected fuel bill at the end. Remember that unforeseen circumstances can crop up from time to time, such as accidents, detours and delays, which might add miles and gas onto your journey. And, on a long trip, there are normally other expenses to consider, such as stops for food and drink, toll fees, and the need to pull in when you see that “best ice cream in the world” sign.


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