The APR on your credit card determines how much interest you'll be charged on your balances. So why pay more if you don't have to? If your credit score reflects your ability to use credit responsibly, then you should at least have an APR equal to other borrowers with your score.
Find out if your card has an APR that's higher than the rate you deserve by checking out cardtrak.com. The site lists the average interest rates for your credit card; for example, the average APR for credit scores 760 or higher is 7.45 percent. If you're paying a rate higher than the average, perhaps it's time to call your credit card company and negotiate a lower APR.