Debt Avalanche Calculator
The avalanche method attacks the highest interest rate first, which is mathematically the cheapest way out of debt. Enter your balances and the extra you can add each month.
On top of minimum payments, rolled to the next debt as each clears.
- Total debt today
- $42,200
- Total interest
- $8,645
- Total paid
- $50,845
- Payoff order
- Store card → Credit card → Car loan → Student loan
Avalanche and snowball clear these debts on the same schedule, so pick whichever order you will actually keep to.
Use Left and Right Arrow, Home, or End to inspect data points.
| Method | Debt-free in | Total interest | Total paid | Order |
|---|---|---|---|---|
| Avalanche | 6 yrs 4 mos | $8,645 | $50,845 | Store card → Credit card → Car loan → Student loan |
| Snowball | 6 yrs 4 mos | $8,645 | $50,845 | Store card → Credit card → Car loan → Student loan |
Estimates only — not financial advice. They produce estimates based on the figures you enter and do not account for every fee, tax or change in rate.
- The result is a deterministic estimate from the inputs shown on this page.
- Fees, taxes and real-world terms not represented by an input are excluded.
- Confirm material decisions against original documents or a qualified professional.
The email includes this route only; calculator inputs are not attached.
Why the highest rate goes first
Interest is charged on a balance, so the debt costing you the most per month is not necessarily the biggest one — it is the one with the highest rate. A $2,200 store card at 27% accrues about $50 a month; a $20,000 student loan at 5% accrues about $83. Per dollar of balance, the store card is more than five times as expensive.
The avalanche exploits that directly. Every spare dollar goes where it cancels the most future interest, which is always the highest rate. That ordering is not a heuristic — it is optimal, and no other order can beat it on total cost.
The rollover is what makes it fast
The avalanche is not just an ordering rule; it is a compounding one. When the first debt clears you do not reclaim its payment — you add it to the next debt's payment, along with your extra amount. Then the next, and the next.
By the final debt you may be paying four or five times the original minimum, which is why the last balances fall far faster than the first. It also means the payoff date is much less sensitive to your extra amount than people expect: even $100 a month sets the rollover in motion.
Where the avalanche struggles
Two situations. If your highest-rate debt is also your largest, the first visible win can be a year or more away, and that is where most payoff plans die. And if rates are tightly clustered, the mathematical advantage over the snowball is small enough that motivation should decide it.
A reasonable hybrid: clear one small balance first for the psychological win, then switch to strict avalanche for everything else. It costs a little and it substantially raises the odds that you finish.
Rates change, so re-run it
Variable-rate credit card APRs move with the prime rate, promotional 0% periods expire, and a balance transfer can reshuffle the whole ordering overnight. The optimal target today may not be the optimal target in six months.
Re-run the plan whenever a rate changes materially, a promotional period ends, or you take on new debt. The avalanche only stays optimal if the ordering reflects current rates.