Payoff comparison and monthly debt balance
The regular budget equals the original total minimum payments plus your monthly extra. Freed minimum payments stay in that budget. Interest and total paid describe the selected strategy; both comparison payoff times use identical starting debts and extra payments. An unpaid balance means the bounded model did not finish.
To solve a fixed monthly payment for a single card and target date, use the Credit Card Payoff Calculator .
The formula
Interest is rounded half up to the nearest cent for each debt each month. Pay current minimums, then apply the remaining budget to the selected priority order. Unused payment money moves to another debt in the same month; a finished debt releases its minimum payment into future months.
Two debts with a zero-interest comparison
Enter First | 100 | 0 | 10 and Second | 200 | 0 | 20, with 30 extra each month. The total budget is 60. Both strategies pay the 300 total in five months, with zero interest and a final balance of zero. The smallest debt finishes first under snowball.
How to use this calculator
- Add a row for each debt’s current balance, APR and actual minimum monthly payment.
- Enter a monthly extra amount you can keep paying after a debt is cleared.
- Choose Snowball, Avalanche or Order entered.
- Compare snowball and avalanche side by side, check when each debt is paid off, then inspect the selected monthly schedule or download it as CSV.
Choose an order while keeping the same budget
Snowball prioritizes the smallest starting balance. Avalanche prioritizes the highest APR. Order entered follows your row order. Minimum payments go to every open debt first; the remaining money then follows the selected priorities. Tie-breaking is deterministic, using APR or balance and then row order.
Clearing a balance does not reduce this model’s regular payment budget. Its old minimum joins the extra amount available to the remaining debts. If a target needs less than the money available, the surplus pays the next target immediately, avoiding an artificial extra month.
Read a payment plan as an estimate
Enter the balance owed now rather than the original loan amount. The model holds APRs and minimum amounts fixed. Update the entries if your lender changes either figure. A one-time extra payment is added only in the selected payment month, while regular extras apply every month.
Monthly interest is a simplification of lender billing. Daily accrual, promotional expiration, new borrowing, fees and statement-specific minimum formulas can change an actual payoff schedule. All debts share one modeled payment date. The calculation stops after 1,200 months and reports any remaining debt instead of inventing a payoff date.
Assumptions & limitations
What this calculation assumes
- All entered amounts use one currency, with no conversion.
- Rates and minimum monthly amounts stay constant; no new borrowing or fees are added.
What to keep in mind
- Use 1–20 uniquely named debts with positive balances and minimums, APRs from 0% to 100%, and at most two decimals.
- The model excludes daily lender interest, changing rates, due-date calendars and changing minimum formulas.
- A projection that has not cleared all debts within 1,200 months reports an unpaid balance.
Common questions
Does the monthly budget fall after I pay off a debt?
No. Freed minimum payments are rolled into the same original monthly budget until the last debt is cleared.
Can I compare both strategies without entering the debts twice?
Yes. Snowball and avalanche are calculated from the same rows, monthly extra and one-time payment. The detailed schedule follows your selected strategy.
What if my payment does not clear the debt?
The tool reports that the plan did not finish in the model and shows the unpaid balance. Increase the payment or check the debt entries before treating the projection as a plan.
Sources & further reading
Reviewed on