Credit card debt has a nasty way of setting you back money-wise. This Federal Reserve calculator (yes, U.S. government Web sites have lots of useful information!) can help you come up with a strategy to pay it down.
You first enter your total balance and interest rate to view how long it would take, and how much interest you would pay, if you just make minimum payments. In the next step, you can find out how to pay it off sooner, either within a certain time period, or by making specific monthly payments.