How the payoff schedule is built
Enter each balance, annual nominal rate and fixed planned minimum. The calculator posts each debt's monthly interest as opening balance × annual rate / 12 and rounds it half-up to cents. It then pays every active minimum, applies targeted windfalls, and allocates the remaining strategy pool. A fixed recurring budget stays available as debts clear.
For a $1,000 zero-rate debt and $250 monthly budget, the modeled payments are $250 in four periods. If an extra $250 posts in month two, payments become $250, $500 and $250. An event is monthly, after interest; an exact posting day is not modeled.
Snowball, avalanche and custom order
Snowball sends extra money to the smallest opening balance, breaking ties by higher rate and stable ID. Avalanche chooses the highest nominal rate, breaking ties by smaller balance and stable ID. Custom follows your row order. All three comparisons use identical debts, recurring budget and extra events. The separately labelled fixed-minimum-only baseline has no rollover and is not a same-budget contest.
What the estimate cannot promise
A lender may compute interest daily, change the minimum payment, add charges or use a different payoff posting order. This monthly model does not predict an exact lender settlement quote. A budget below the active fixed minimums is flagged rather than silently starving a debt. If balances remain after 600 months, the result says so and shows the remaining balance instead of inventing a payoff date.
Frequently asked questions
Can I target my tax refund to one card?
Yes. Add a one-time extra for that month and choose the debt. Any amount left after it clears moves into the strategy pool.
Is avalanche always best for me?
It is a modelled interest-priority approach, not personalized financial advice. Compare schedules with your actual lender terms.
Have only one loan?
The Amortization Calculator focuses on a single loan's scheduled payments.