Debt payoff calculator
Paid off in 2 years, 11 months. The extra $50.00 a month saves $687.03 in interest and finishes 9 months sooner than $250.00 alone. Interest is charged once a month on the remaining balance. The 18% rate is an example. Enter the APR on your statement for a debt of your own.
How this is calculated
Each month, interest equals the remaining balance times the annual rate divided by 12. Whatever is left of the payment reduces the balance. The last payment is smaller, because it covers only what is left plus that month's interest. If the payment is less than or equal to the first month's interest, the balance does not fall, and the result says so instead of showing a payoff date.
An extra monthly payment is added to the regular payment and compared with paying only the regular amount.
- One debt, one fixed payment, one constant APR.
- Interest is charged once a month, not daily. Many credit cards divide the APR by 365 and charge it daily, which costs slightly more than this estimate.
- Fees and promotional rates that expire are not included.
- Totals are rounded to the cent at the end. A lender that rounds every month can differ by a few cents.
- With more than one debt, avalanche applies extra money to the highest rate and snowball applies it to the smallest balance. This page does not model that choice.
Questions
Why does a small extra payment change the total?
Early on, most of a payment is interest. Extra money reduces the balance, and every later month charges interest on less. The comparison in the result is that effect for the numbers you entered. It is not a promise about a different debt.
What if my payment does not cover the interest?
The balance does not fall, so there is no honest payoff date to show. The result states the first month's interest. A payment has to be above that number before the balance starts down.
Is this my credit card's minimum payment?
No. A minimum payment is often a percentage of the balance plus interest, so it shrinks as you pay and the debt lingers. This calculator uses a fixed amount: the amount you choose to send each month.
Avalanche or snowball?
For a single debt they are the same thing. For several debts, avalanche puts extra money toward the highest rate and pays less interest. Snowball puts it toward the smallest balance and clears one debt sooner. This calculator models one balance. The guide linked below walks through both methods.
Learn the ideas behind the formula
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