During law school I had unfortunately accumulated a decent amount of credit card debt. This calculator helped me to pay down all my credit card debt in a short time.
The snowball method helps users pay down multiple credit cards in a way that minimizes the interest payments. It asks for details including interest rates, minimum payments, and any special rate sunsets and then asks how much you can afford to pay to each card. The spreadsheet will then give you the amount to pay to each card each month as well as showing you a graph forecasting the slowly diminishing interest payment you will be making each month.
I’m surprised its not already up here! (Pro-tip: this debt-reduction method, in conjunction with a negotiating session or three with the the banks holding your largest, highest interest rate cards, can save you a lot of money.)