Debt Payoff Tool
Estimate when multiple debts will be cleared using minimum payments, monthly extras and optional lump sums. Compare avalanche, snowball or listed-order repayment priorities, explore interest savings and repayment schedules, and export detailed results for further review.
| Month | Date | Paid | Interest | Principal | Balance |
|---|
Table of Contents
Highlights
- Compare avalanche, snowball and custom listed repayment order.
- Model up to 30 debts with individual APRs and minimums.
- Add recurring extra payments or a timed one-off lump sum.
- View payoff dates, interest savings and comparative balance charts.
- Export repayment schedules, debt summaries, JSON data and SVG charts.
How Debt Payoff Tool Works?
Each debt begins with a balance, annual percentage rate (APR) and fixed minimum monthly payment. The chosen start month establishes calendar labels. For every month, interest is added to each outstanding balance, scheduled minimum payments are applied, then remaining available money is directed to debts in priority order.
Here APR is entered as a percentage and interest is rounded to two decimal places each month. A debt's new balance is its previous balance plus monthly interest less payments, with the final payment capped at the outstanding amount.
| Option | How it changes repayment order or budget |
|---|---|
| Avalanche | Directs surplus payments towards the outstanding debt with the highest APR. |
| Snowball | Directs surplus payments towards the outstanding debt with the smallest remaining balance. |
| Listed order | Prioritises debts in their entered order. |
| Monthly extra | Adds the stated amount to each month's payment budget. |
| One-off extra | Adds a lump sum in the selected repayment month. |
| Roll freed minimums | Retains the original combined minimum-payment budget after individual debts are cleared; when off, the budget falls as debts finish. |
A second schedule uses only each active debt's minimum payment, without additional payments or budget rollover. The difference between that schedule's total interest and the selected plan's total interest produces estimated interest savings. The results include months to payoff, payoff date, total debt, interest, overall payments, initial monthly budget, debt-specific payoff details, a comparative balance chart and a monthly interest/principal/balance table.
Practical Use Cases
Credit card holders: Compare repaying several cards by highest APR versus smallest remaining balance, and see how an extra monthly payment affects debt-free dates and interest charges.
Personal loan borrowers: Combine a personal loan with cards or store accounts, keeping each loan's balance, APR and fixed minimum payment separate to plan total household repayments.
Household budget planners: Enter an affordable extra monthly amount and choose whether to redirect freed minimum payments to remaining balances, then examine the projected monthly repayment table.
Bonus recipients: Enter an expected one-off payment and its month to estimate how a bonus, refund or windfall could shorten the remaining repayment period.
Financial advisers and debt coaches: Demonstrate alternative repayment priorities, inspect debt-by-debt interest totals and export a CSV schedule or JSON results for client discussions.
Accuracy and Limitations
Results are deterministic estimates based on a constant APR for each debt, monthly interest calculated as balance × APR ÷ 1200, two-decimal rounding and payments applied after monthly interest. Minimum payments are fixed amounts, not issuer-defined percentages or declining contractual schedules. The model excludes fees, penalties, taxes, new borrowing, promotional APR changes, daily interest accrual and payment-date differences. It supports up to 30 debts and a maximum 1,200-month schedule, rejecting plans that cannot clear within that limit; it also rejects minimum payments below the first month's calculated interest. The minimum-payment comparison is a simulation, not a lender quote.
