Debt Payoff Calculator
Enter up to five debts and your extra monthly amount to see avalanche vs snowball head-to-head: payoff time, total interest, and the winner.
How your highest APR compares
Your highest card APR vs. the national average
💸 A lower-APR consolidation loan can speed this up
Check your rateAvalanche vs snowball
Both strategies pay every minimum, throw everything extra at one target debt, and roll each freed-up payment into the next target. They differ only in the order: the avalanche hits the highest APR first, which minimizes total interest by pure arithmetic; the snowball hits the smallest balance first, which delivers the fastest first win and keeps motivation alive.
The gap is usually smaller than people expect — pick the plan you will actually follow, with the price tag in view.
How it’s calculated
Each month every debt accrues interest at APR ÷ 12. Your budget (minimums + extra) is fixed: minimums first, the remainder to the target debt — highest APR (avalanche) or smallest balance (snowball) — with freed-up payments rolling forward until all balances are zero.
Assumes fixed APRs, no new charges, and no fees or penalty-rate changes. Estimates only — not financial advice.
Payoff order
Both strategies use the same fixed monthly budget.
Worked example
Three debts — $8,000 at 22% (min $200), $12,000 at 7% (min $260), $5,000 at 11% (min $150) — plus $150 extra is a $760 budget. The avalanche finishes in 40 months with $5,212 of interest; the snowball takes 41 months and $5,890 — avalanche wins by $679. With no extra, payoff takes 56 months and $8,711.
Common mistakes
- Letting freed-up payments drift back into spending.
- Ranking by balance when one APR is triple the others — price the snowball first.
- Draining the emergency fund, then re-borrowing at card rates when life happens.
Where it is used
- Building a payoff plan for a mix of cards and loans.
- Deciding if consolidation or a 0% balance transfer beats the DIY route.
- Budgeting sessions that need concrete payoff dates.
Frequently asked questions
Which is better, avalanche or snowball?
The avalanche (highest APR first) always costs the same or less — $679 less here. The snowball (smallest balance first) wins on motivation. Pick the one you will stick with.
How much does the extra payment help?
Every extra dollar attacks principal: $150 extra cuts payoff from 56 to 40 months and interest from $8,711 to $5,212.
What happens to a payment after its debt is gone?
Your budget stays fixed: once a debt is cleared, its payment rolls into the target debt. That rollover is the engine of both strategies.
What if my budget doesn't cover the interest?
Balances grow instead of shrinking, and the calculator flags that payoff never happens. Fixes: pay more, negotiate rates, or consolidate at a lower APR.