Debt Snowball vs Avalanche Calculator
Simulate paying off your debts with the avalanche (highest rate first) and snowball (smallest balance first) methods side by side, month by month.
Last reviewed
Avalanche pays extra toward your highest-interest debt first; snowball pays extra toward your smallest balance first. Both simulate every debt's minimum payment plus a fixed extra amount, month by month, rolling each paid-off debt's freed-up minimum into the next target. This calculator runs both orders on your actual debts and shows which one costs less and by how much.
Interest Saved with Avalanche
$162
Months to Debt-Free
26 mo
Months to Debt-Free
26 mo
Your Debts
Extra Monthly Payment
Total Balance Over Time
Avalanche vs. Snowball
Avalanche Payoff Order
- Credit Card A
- Credit Card B
- Personal Loan
Snowball Payoff Order
- Credit Card B
- Credit Card A
- Personal Loan
Same Money, Different Order
Both strategies spend the exact same total amount each month: every debt's minimum, plus a fixed extra payment aimed at one debt at a time. The only thing that changes is which debt gets the extra money first. Once that debt is paid off, its minimum payment joins the extra amount and rolls onto the next one, so the total monthly outlay never drops until everything is paid off.
Avalanche always produces the lowest or tied-lowest total interest, because it attacks the balance accruing interest fastest. Snowball can cost a little more in interest, but clears individual debts sooner, which is the entire behavioral case for it: a plan you actually finish beats a technically-optimal plan you abandon.
Each Month, Per Debt
A Worked Example
Using this calculator's default three debts (a $5,000 card at 24.99% with $125/mo minimum, a $2,500 card at 18.99% with $75/mo minimum, and an $8,000 personal loan at 11.5% with $220/mo minimum) plus a $300 extra payment, both strategies pay off all three debts in 26 months. Avalanche (attacking the 24.99% card first) costs $2,727.01 in total interest; snowball (attacking the $2,500 balance first, which also happens to be the middle-rate debt) costs $2,889.25. Avalanche saves $162.24 in this case, a real but modest difference common when balances and rates don't line up in the same order.
The payoff time matches for both strategies in this example because the total monthly budget ($125 + $75 + $220 + $300 = $720) and total starting debt ($15,500) are identical either way. Only the interest cost changes with the order. That won't always be true; when one debt's rate is far higher than the others, avalanche both saves more interest and often finishes sooner too.
What This Doesn't Cover
This assumes fixed minimum payments and a fixed extra amount for the entire payoff. There are no missed payments, new charges, changing rates (variable-rate cards can reprice), or windfalls applied early. It also doesn't account for the psychological cost of sticking with a plan, which is exactly why snowball exists as an alternative to the mathematically optimal avalanche order. If a debt's minimum doesn't cover its own accruing interest, this calculator flags it directly rather than showing a payoff date that will never arrive on the current terms.
Payoff Strategy Inquiries
?What's the actual difference between avalanche and snowball?
Both pay every debt's minimum every month, then throw all extra cash at exactly one debt at a time. Avalanche targets the highest interest rate first, minimizing total interest paid. Snowball targets the smallest balance first, clearing individual debts faster and often being easier to stick with psychologically. Whichever debt gets paid off first, its minimum payment 'rolls over' and joins the extra amount going toward the next target.
?Why would I ever pick snowball if avalanche saves more money?
Because the math only works if you actually follow the plan for months or years. Snowball's early wins (a whole debt gone in month 3 or 4) build momentum that keeps some people on track when avalanche's slower first payoff doesn't. If you're confident you'll stick with either, avalanche is mathematically better. If you've stalled out before, the behavioral edge of snowball can outweigh a modest interest difference.
?What does the warning about minimum payments mean?
If a debt's minimum payment is less than the interest accruing on it that month, the balance grows even while you're paying (a form of negative amortization). This calculator flags any such debt directly, since no amount of waiting fixes it; only extra payments above the interest, or a lower rate, will.
?Does this include extra payments that increase over time (like a raise)?
No. This models a fixed monthly extra-payment amount for the life of the payoff. If your available extra payment grows, you'll pay off debt faster than shown here; treat these numbers as a conservative baseline.
?Why does the simulation cap at 600 months?
600 months is 50 years, long enough to cover any realistic payoff. It serves as a hard stop that keeps the calculator from running forever if your inputs describe a debt that mathematically never gets paid off (minimums below accruing interest with no extra payment to offset it).
About this calculator. Results are estimates for education and planning, based on the inputs you enter and the published formula described above. Everything runs in your browser; nothing you type is sent to us or stored. It is not financial, tax, legal or medical advice. Read the disclaimer and our methodology.
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