How to Calculate the Cost of Driving

With gas prices soaring in the US and around the globe, the cost to drive to a vacation destination is becoming a much larger expense item in the overall travel budget.  Although it's easy to see that gas prices have risen dramatically in the past several months, it's not nearly as easy to figured out how it will impact that upcoming car trip, so here are the items you need to take into consideration to calculate how much it will cost to drive to a destination.

• Price of Gas: The obvious piece of information you'll need to know is the price of gasoline where you will fill up your car, both at the start of a trip and at refueling points along the way.
• MPG: The next step is to determine the fuel efficiency of the vehicle you will be driving, otherwise known as the MPG (miles per gallon).  Although there are generally three MPG ratings for a car (city, highway and combined), for trips that are mostly on highways the highway MPG should be used.  Otherwise, use the combined MPG.

Tips

• If you don't know the fuel efficiency of your car, you can find that information on the EPA's fueleconomy.gov website.
• Distance: The distance in miles of the trip, which can easily be obtained in the driving directions of any of the popular mapping sites such as Google Maps and MapQuest.
• Fuel Tank Capacity: You also need to understand how far your vehicle will travel on a single tank of fuel, which is known as the range of the vehicle.  The range is a factor of the gas tank size multiplied by the MPG.

Warnings

• There are other items that factor into the cost of driving, such as tolls, maintenance, dining and lodging, but for this article we'll just focus on the fuel costs.

The Calculation: For the sake of simplicity, lets say you are taking a 200-mile trip in a vehicle that has a range of 300 miles, therefore refueling is not required and you do not need to factor in the fuel tank capacity or gas prices along the route.  If the price of gas is $3.50 per gallon at the starting point, and if the MPG is 30, then the calculation is as follows: Distance (200) divided by MPG (30) multiplied by Price of Gas ($3.50).

• (200/30) x $3.50 = $23.33 Trip Cost

A much easier way to calculate the cost of driving is to use Cost2Drive.com, a site that automatically calculates the fuel costs for driving anywhere in the US based on real time gas prices along the route.  

With the Cost2Drive trip calculator, all you need to enter is the starting and ending points for your trip and then select the type of vehicle you will be driving.  The 'galculator' on Cost2Drive automatically determines the MPG and fuel tank capacity of your vehicle as well as the fuel type (regular, premium or diesel) based on a vehicle database of over 20,000 cars and trucks.  Then, using the Google Maps service, Cost2Drive will plot out the refueling points along your route and locate the cheapest gas at those points for over 80,000 stations across the US.

Cost2Drive also includes an innovative cost comparison feature that displays a link to the cheapest flight for the route on Kayak.com.  This makes it easy to see if it's cheaper to drive or fly to the destination.

Warnings

• These costs are only estimates, as there are many variables that can impact the fuel efficiency of a vehicle, such as traffic, weather and personal driving habits.