How do I calculate when I'll be debt free?
You need three numbers: your total balance, the total you pay toward it each month, and your interest rate. From those, the payoff month is fixed — interest accrues on the remaining balance each month, your payment knocks it down, and the date is however long that takes to reach zero.
Enter them above and you'll have the answer immediately. If you don't know your exact rate, leave it blank — the calculator assumes 22%, which is close to a typical credit card, and states that assumption next to the field.