Methodology
Each month, the calculator computes interest for every active debt using that debt's APR divided by 12. Credit card payments use the greater of the entered minimum, $25, or 1% of the current balance plus that month's interest, capped at the amount needed to pay the card off that month. Installment loans use the fixed monthly payment you entered, also capped at payoff.
Payments first cover that month's interest, then reduce principal. If you enter an extra payment, the calculator pays every active card minimum and loan payment first, then sends remaining money to the selected payoff strategy. If you enter a total monthly payoff budget, the calculator treats that amount as the planned total payment, but future required minimums or fixed loan payments can make the actual monthly payment higher.
Avalanche targets the highest APR debt first. Snowball targets the smallest active balance first. Custom order follows the list you set. Paying minimums only applies no extra payment. When promotional APRs are entered, the promo rate applies through the entered promo months, then the standard APR applies.
Balance transfer and consolidation loan scenarios only move current credit card debt. If entered offer capacity is greater than eligible card debt, the unused capacity is reported but not modeled as new borrowing. Entered transfer and origination fees are added to the modeled new balance, and the offer model tests offer orders using the selected payoff strategy, projected interest, fees, promo expirations, and loan terms.
The schedule stops when all balances reach $0 or after 600 months. Results are estimates and do not include new purchases, late fees, annual fees, mid-cycle timing changes, penalty APRs, payment posting differences, or issuer-specific minimum rules beyond the model above.
FAQ
What payment do I need to be debt-free by a target month?
Enter a target payoff month. The calculator searches total monthly payoff amounts and reports the smallest estimated payment that pays all entered debts by that month. If future minimums or fixed loan payments exceed that amount, it shows the higher required monthly payment.
What is the debt avalanche method?
Avalanche pays every debt's minimum, then sends extra money to the highest APR debt. It is usually the lowest-interest method.
What is the debt snowball method?
Snowball pays every debt's minimum, then sends extra money to the smallest balance. It may cost more interest, but it can produce a faster first payoff.
Why do minimum payments sometimes show a warning?
If a debt's minimum payment is less than or equal to the monthly interest charge, principal does not shrink. The calculator flags that as a minimum-payment warning.
Can I use this offline?
Yes. The calculator math runs in your browser and can keep working after the page loads. User-submitted feedback may not work while offline.