You Are Miscalculating Gas Costs for Your Road Trip. Here’s How to Do It Right

Road trips are pure, unadulterated fun.

If you are curious and want to know more about the areas around you, there is nothing better than a road trip.

The only downside is that gas prices have increased ridiculously over the years.

If you are going on a road trip, you have to plan ahead for fuel costs.

Here are a few tips on how to do that:

How to Calculate Gas Costs for Your Road Trip 

It seems like a no-brainer, until you realize that it isn’t. Road trips can be savagely expensive if you have not taken this into account.

1. Calculate miles per gallon

This is something you have to figure out on your own. What is written in brochures and manuals might not always be correct.

It is best to work mileage out the old-fashioned way.

  • Fill your tank up all the way and set the trip meter to zero.
  • Drive around as usual.
  • When you fill up next, note the mileage on the trip meter and how many gallons you put in.
  • Divide the miles by the gallons and you have your miles per gallon.

For example, if you were to fill up your tank today and sets the trip meter to zero, and then after a week, you fill the car up again and find the trip meter reads 89. You fill the car up with 3.7 gallons.

Your MPG is 89 ÷ 3.7 = 24

Of course, it might be miles per liter or kilometers per liter, depending on where you are and your personal preference.

2. Figure out the distance

You may be traveling directly from point A to B, or making several pit stops. Whatever your itinerary, Google Maps is invaluable for calculating distance.

Open the Google Maps app and type in the start point and destination.

After you type in the first destination, you can add more if needed. In that case, make the final destination the last to be added.

If you are planning a trip, you can do it from a smartphone, but it is better if you use a laptop and export the trip to a phone. The bigger screen gives you a more solid idea of alternative routes.

3. Gas price optimization

Gas prices vary considerably across the world. Not only do prices follow the price of oil, but they also tend to peak near holiday weekends.

The time around Memorial Day in the U.S. is particularly expensive. It is the beginning of summer, and most Americans are heading out on vacations.

There are plenty of smart ways to save on gas, though.

  • Use apps to find the cheapest gas near you. Though several apps claim to locate the cheapest gas, GasBuddy has been the most popular for about a decade. It tracks prices at 100,000 stations in the continental U.S. and Canada.
  • The price of gas can vary significantly across U.S. states. Pennsylvania is notoriously expensive, with a tax of about 70 cents to a gallon. New York and California, too, are known for steep prices.
  • Skip buying premium. Regular gasoline can save you about 40 cents for every gallon.
  • Join a membership program. On average, they offer about 25 cents off the price of a gallon. Exxon Mobil, BP, and Maverik are some of the most well-known programs. GasBuddy also offers its own discounting plans.
  • Get a credit card with a gasoline reward feature. Blue Cash from American Express provides a 3% discount at the pump, and 6% at supermarkets. Sam’s Club Mastercard gives a 5% rebate on fuel.

4. Calculate trip cost

Now you know the mileage, distance, and average cost of gas. Use the formula (distance ÷ miles) * cost per gallon.

For example, Pennington, New Jersey to Niagara, New York, through Wellsboro, Pennsylvania, is 430 miles.

If your car gets 24 MPG and required 18 gallons, at $2.65 per gallon with a Sam’s Club card, you would pay 18 * 2.65 = $48 approximately. Of course, calculations are seldom perfect, so add a 10% overhead and budget for $55. A round trip would be slightly more than $100.

Tips to Save Fuel

The best way to save on fuel costs is to save on fuel consumption.

  • Plan your trip with as few pit stops as possible. Every time you stop, your car uses a bit of extra fuel to get back up to speed. On the highway, anticipate where you are going in the next few hundred yards. Slowing down after speeding up would cause needless fuel consumption.
  • Ensure that tire pressure is optimum and the car is well maintained. If you are driving at a constant speed, use the cruise control feature.
  • Don’t speed unnecessarily. More speed means more friction due to air and more horsepower for minimal speed increases. Unless you are driving a sports car, the best speed is about 70 mph.

For International Trips

If your road trip is going to take you across several countries, it’s important to keep in mind that the gasoline you fill up with could be different. Due to emissions laws, some countries require gasoline to contain a certain minimum level of ethanol, which is derived primarily from corn. In the U.S., regular unleaded gasoline has around 10% ethanol. However, in some countries, gasoline can contain up to 83% ethanol.

This is important from a fuel economy perspective. While high-ethanol fuels can produce fewer emissions and are sometime cheaper, they impact gas mileage. E85 fuel (gasoline containing high amounts of ethanol) can result in more than a 20% drop in fuel economy. This means that your car that typically gets 24 MPG might only get around 19 MPG when running on E85. It can also cause damage to vehicles not designed to run on high-ethanol fuels. Keep this in mind when planning fuel stops, so you do not risk running out of gas or damaging your vehicle.

Get Insurance Before You Hit the Road

A road trip can be fun for the whole family, but accidents do happen. In 2019 there were over 33,000 road accidents in the USA.

Other than driving safely and being alert, you could and should buy travel insurance before your trip. A travel insurance policy can provide coverage for emergency medical issues, trip cancellations, travel delays, and other valuable benefits

With Insubuy, you can find exceptional road trip insurance policies that can be easily compared side by side. If you need personalized advice, you have the option to call customer support. Helpful staff can guide you through the buying process and ensure that you are protected at the most affordable price possible.


You do have to remember that planning offers estimates, not actuals. There might be unplanned delays and detours that throw a wrench into the works.

The price of gas is only one part of the expenses of traveling. There will be meals, beverages, and of course, a lot of treats to pay for.

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