How the debt payoff calculator works
Each month, interest is added to your balance and your payment is applied. Whatever is left after covering that month's interest goes to reducing the principal. We repeat this until the balance reaches zero, then report how long it took and how much interest you paid along the way.
months = −ln(1 − iB ÷ P) ÷ ln(1 + i)
B = balance · i = monthly rate (APR ÷ 12) · P = monthly payment
The interest trap
On high-rate debt like credit cards, a large share of a small payment goes straight to interest. If your payment barely exceeds the monthly interest, payoff can take years. Raising the payment, or lowering the rate, dramatically shortens it.
Frequently asked questions
Why won't my balance go down?
If your monthly payment is less than or equal to the monthly interest, the balance never falls. You must pay more than the interest each month to make progress. The calculator flags this case.
How can I pay off debt faster?
Increase your monthly payment, lower the rate by consolidating into a personal loan or a balance transfer, or both. Even a modest payment increase can cut many months and a lot of interest.
Snowball or avalanche?
The avalanche method (highest interest rate first) saves the most money. The snowball method (smallest balance first) gives quicker wins for motivation. Both work; pick the one you'll stick with.
Does consolidating actually help?
It can, if the new rate is meaningfully lower and you don't run the old balances back up. Replacing 20%+ card debt with a lower-rate loan reduces the interest you pay and can shorten the payoff.
Estimates only, not financial advice. Confirm figures with your lender.