What you pay will vary depending on your balance, the interest rate and the way your finance charge is calculated. Here's an example that shows
High-rate card - Suppose you charge $1,000 on a 23.99-percent credit card. After that, you make no further charges and pay only the minimum each month. The payment will start at $51 and slowly work its way down to $10. You'll make 77 payments over the next six years and five months. By then, you will have paid $573.59 in interest for your credit privilege.
Low-rate card - If you charge that same $1,000 on a 9.9-percent fixed-rate card, the minimum monthly payment will start at $50.41 and go down to $10. You'll make 17 fewer payments, finishing in six years and paying $176 in interest. This saves you almost $400!
How do they get $51 from 5%, 23.99%, and $1000. Likewise for the second one.