Road Trip Gas Calculator | How to estimate your travel budget

Whether you’re planning a cross country road trip or a college tour, or even a trip to your new home during a relocation, it’s important to know just how far your car will take you on a tank of gas. For this purpose, you need to find out how a road trip gas calculator works. Planning your budget can go a long way to providing peace of mind not only during your trip, but it can provide valuable information that can help you make wise decisions regarding your finances. 

The fuel price fluctuates based on a range of factors, such as:


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road trip gas calculator

How to Calculate Gas Costs

If you’re wondering how to calculate how far you can go on a tank of gas, you first need to determine your vehicle’s estimated miles per gallon, both in the city and on highways. A road trip gas calculator will take this aspect into account. The capacity of your car’s gas tank also plays a role. You can use these figures to calculate a weighted average based on your typical driving habits, and find out how far you can go on a tank of gas. Any good road trip gas calculator takes into consideration:

When you know the gas price per gallon, a road trip gas calculator will simply multiply that by the distance in miles of the trip to reach a final price for your trip. However, it is important to note that your trip will cost more than just gas. There’s also:


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Step 1: Determine your car’s miles per gallon

There are several different ways to find out how many miles you can get per gallon of gas. Sites like FuelEconomy.com provide estimates for most types of car and it has a handy road trip gas calculator. Note, however, that those are averages for that vehicle and model and do not take into account your driving habits on different roads.  A better way to get a more accurate reading is to calculate it manually, but for this, you need some time ahead of your road trip. 

To manually calculate your miles per gallon, fill up the gas tank, and set your trip odometer to zero on the instrument panel. Now you need to simply drive as per normal. When it is time to fill up again, take note of the trip odometer reading. This will show you how many miles you’ve driven since you last filled up. If your car is older and does not have a trip odometer, you can simply write down your overall odometer reading and when you fill up, your latest reading. The difference between the two will be the number of miles driven since your last fill up. 

Step 2: Calculate the trip distance

How long will your cross country road trip be? A bit of road trip planning will provide valuable information. You can use a road trip gas calculator or do the following.

Start by opening up Google Maps on your phone, and enter your destination. Use the tool to find the total amount of miles. While you are here, you might as well look at:

Finally, note the distance of your trip to factor it into your mile per gallon calculations. 

Step 3: Check on the price of gas

The gas price is not consistent; it varies by time, by region and other factors. Even if you remember the price from the last time you filled up, it can fluctuate before you fill up for your road trip. The AAA provides current regional and national gas prices to use in your road trip gas calculator. This might give you an indication as to what you can expect to pay. 

Interesting fact: Did you know that the average American spends approximately $3,000 per year in gas?

Now that you know the price of gas, your trip distance, and your car’s miles per gallon, you can easily calculate the gas costs of your trip. Remember to factor in the wear and tear to your car if you’re driving across the country. It is often a better idea to rent a car on a round trip or one-way car rental contract, as that will not add any wear and tear to your car and you will alleviate the hassles of driving with an older – less reliable – car.

The road trip gas calculator will now divide the distance of your trip by the miles per gallon you get from your car. The answer will tell you how many miles you will get from each mile. From there, multiply the number of gallons by the gas price to calculate how much gas you will need for the trip. 

Additionally, knowing the cost of gas for your trip is handy as you won’t be stuck with an unexpected fuel bill. 

Not too good at math? You could use one of these road trip gas calculators:

road trip gas calculator

How to Save Gas on Your Road Trip

Although gas is a major expense for drivers, the price goes up and down, and there are practical steps to use if you would like to save some money on fuel. 

  1. Rent an electric car to completely alleviate the cost of fuel. However, the cost of electricity may also fluctuate based on similar issues as gasoline. 
  2. Buy or rent a more fuel efficient car. Instead of a gas guzzling SUV, opt for a smaller sedan. You will see the difference when you enter information in a road trip gas calculator.
  3. Carpool. Two people traveling in one car use less fuel than two people traveling in the same direction in two separate cars. 
  4. Plan your trip carefully. The longer your trip, the more fuel you will use, obviously. However, while planning your trip, pay attention to things like choosing routes with fewer stops and diversions. Highways use less fuel than city streets, so choose those whenever possible. Always choose routes that offer a steady speed, as that maximizes fuel efficiency than stop and go city traffic. 

More Gas Save Tips

  1. Using the correct motor oil can improve your gas mileage by up to two percent. Consult your manufacturer’s guide book to find out which oil is most suited to your engine, and opt for one that is marked as ‘energy conserving’.
  2. Tires that are properly inflated can help reduce your fuel consumption by as much as three percent. On average, tires lose approximately 1 PSI per month. During winter, the pressure also decreases as a result of the thermal contraction of the air. Always check your tires once a month,  or once a week. Properly inflated tires are also important to preventing uneven wear. Inflate your tires according to the car manufacturer’s recommendation, rather than to the level stamped on the tire.
  3. Tuning the engine is another way to ensure that your vehicle is more fuel efficient, as it maximizes the power of your vehicle. If your car has failed an emissions test or is out of tune, you can still improve its mileage. Regular maintenance and servicing will help improve your fuel efficiency, while aerodynamics kits, air foils, ground effects and deck lid spoilers will only increase your car’s drag, which uses more fuel.

Road Trip Gas Calculator & Rental Cars

A great way to save on travel costs is to rent a car. Firstly, you don’t add wear and tear to your car, but you also save on fuel costs when you rent a car with unlimited miles. Most car rental companies offer unlimited car rentals, which means that they allow you to pay only for the daily rental costs, insurance and extras, and not for each mile traveled based on the average rate of fuel per mile. 

A road trip gas calculator is a helpful tool for quickly and easily determine how much money you need to set aside for fuel during your road trip.