Snowball and avalanche use the exact same extra dollars each month, they just disagree on which debt those dollars should hit first, and that single choice changes both your timeline and your total interest.
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Debt Payoff Calculator
Compare the snowball and avalanche methods side by side, see which debt to attack first, and your real debt-free date.
Snowball smallest balance first
Avalanche highest APR first
Assumes each debt's APR stays fixed and every extra dollar goes to one debt at a time. Runs entirely in your browser, nothing about your debts is sent anywhere.
How the simulation works
Each month, every debt accrues interest at its own APR ÷ 12, then every debt gets its minimum payment, then whatever's left of your budget (your extra amount, plus the minimum payments of any debts you've already paid off) goes entirely to whichever debt is next in priority order. That's simulated month by month until every balance hits zero, which is the only accurate way to model payments cascading between debts as each one closes out.
Debt payoff calculator FAQ
What is the difference between debt snowball and debt avalanche?
Both pay the minimum on every debt and throw every spare dollar at just one debt at a time. Snowball targets your smallest balance first, avalanche targets your highest interest rate first. Avalanche is mathematically guaranteed to cost you the same or less in total interest; snowball is built around psychology, clearing a whole account fast builds momentum that keeps some people going.
So which one should I actually use?
If you're confident you'll stick with a plan either way, avalanche saves real money and there's no reason not to use it. If you've stalled out on debt payoff before, the quick wins from snowball closing out whole accounts may matter more to you than the extra interest, sticking with a plan you'll actually follow beats a theoretically optimal one you abandon in month three.
What if a debt's minimum payment doesn't even cover the interest?
That debt's balance grows every month no matter which strategy you pick, and it will never reach zero on minimum payments alone. This calculator flags that case directly rather than showing a payoff date centuries away, if you see that warning, that debt needs extra payment routed to it immediately.
Does this handle variable interest rates?
No, it assumes the APR you enter for each debt stays fixed for the whole payoff period. If a rate changes significantly, especially a promotional 0% period ending, rerun the numbers with the new rate to see how it shifts your payoff date.
Is my debt information private?
Yes. Every simulation runs in your browser. Nothing you enter about your balances or debts is sent to a server, logged, or stored.
Free debt payoff calculator by ANUPRESS
The one rule both methods actually share
Neither strategy changes how much you pay each month. Both pay the minimum on every debt, then take whatever’s left in your budget and throw all of it at exactly one debt, the rest keep getting just their minimum until that first one hits zero. Once it does, its entire minimum payment doesn’t disappear, it rolls straight into the pile of money attacking the next debt in line, which is why the payoff snowballs (or avalanches) faster near the end than at the start.
Why avalanche is the mathematically correct answer
Avalanche always attacks whichever debt currently has the highest interest rate, which by definition is the debt bleeding you the most money every single month it survives. Killing that one first, before it accrues another month of its worst-in-your-portfolio rate, is guaranteed to cost the same or less total interest than any other order you could choose. There’s no version of “pay in a different order” that beats avalanche on pure cost.
Why some people still choose snowball anyway
Snowball ignores interest rates entirely and goes straight for the smallest balance, because closing out a whole account, seeing one fewer bill arrive, one fewer app on your banking dashboard, is a real psychological win that a shrinking-but-still-open balance on your biggest debt doesn’t give you. If a rigid math-optimal plan is one you’ve abandoned before, a method built around early wins that keeps you actually paying extra every month can beat a technically cheaper plan you quit on in month four.
What the comparison number actually means
The amount shown as “avalanche saves you” is the total extra interest snowball would cost across the entire payoff period, not a monthly figure. For a handful of small debts at similar rates, that gap is often small enough that picking whichever method motivates you more is a perfectly reasonable call. For a mix of high and low rate debts, especially anything near typical credit card APRs, the gap can run into real money, worth a look before deciding.