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How to Calculate Fuel Cost

Finding the Current Gas Price
High gas prices are posted at a Shell gas station in Menlo Park, Calif., in 2008.
High gas prices are posted at a Shell gas station in Menlo Park, Calif., in 2008.
AP Photo/Paul Sakuma

Lots of factors can affect the price of gasoline. International supply, taxes, the time of year and even speculation can all cause the price of crude oil (which is processed into gasoline) to fluctuate. In addition, gas is more expensive in some parts of the country than others. California, with its high taxes and large metropolitan areas, often has higher gas prices than the rest of the nation.

For these reasons, it's good to know how expensive gas is locally. If you're traveling to a certain location, it can be helpful to your budget to know approximately how much money you'll need to fill up your rental car. It's also good to know where you can get cheap gas in your own area.

There are many ways to determine the current gas price. AAA runs a Web site that keeps a daily report on fuel prices across the country. You can use it to find the national average, and to search for your own state. At the time of the writing, the site shows that West Coast states are getting hit with the highest gas prices, while states near the Gulf Coast have the cheapest gasoline.

MapQuest also lets you search for gas prices around your local area. Just enter your address and the results will show you a list of gas stations around you, along with how much you'll pay at the pump.

The EPA also maintains a list of links that allow you to find gas prices locally. This is a great resource if you're going to be traveling and can't decide whether your rental car should be a Corvette or perhaps a Prius.

There are many other great resources online also. Smartphones like the iPhone and Android devices, for example, are great on-the-go devices for finding current gas prices, too. You might even save some cash if you take advantage of some of the gas price apps they can run.

Will gas prices get more expensive soon? That's a question on all our minds, whether we're buying a new car or planning a big vacation. Find out on the next page.