Debt Snowball & Avalanche Calculator

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How the Debt Snowball method works

The Debt Snowball orders your debts from smallest balance to largest. Each month you pay the minimum on everything, then put every spare dollar toward the smallest balance. When it’s gone, its minimum payment (plus your extra) rolls onto the next smallest, so the amount put toward each debt keeps growing like a snowball.

Snowball’s strength is momentum: you close whole accounts early and often, and each cleared debt is proof the plan is working. If you’ve started and abandoned payoff plans before, those quick wins matter more than the interest math.

How the Debt Avalanche method works

The Debt Avalanche orders your debts by interest rate, highest APR first. The mechanics are the same (minimums on everything, all spare budget onto one target, freed-up minimums roll forward), but the target is always the debt charging you the most.

That makes Avalanche the mathematically optimal order: on the same monthly budget it never pays more total interest than Snowball, and usually pays less. It asks for patience, though: if your highest-rate debt is also a big one, it can be a long time before you feel the first win.

Snowball vs Avalanche: which should you pick?

Run your numbers in the calculator above and look at the comparison. It answers the question in dollars and months. The gap is often smaller than people expect: when it’s a month or two and a modest amount of interest, pick whichever order you’ll stick with. When the gap is large, usually because a big balance carries a high rate, Avalanche is the better choice.

A popular middle path: start with Snowball to clear one or two small balances fast, then switch to Avalanche for the rest. Every version shares the part that does the work: the constant monthly budget, with every freed-up minimum rolled forward until the last debt falls.

Frequently asked questions

What’s the difference between the Debt Snowball and Debt Avalanche methods?

Only the order you pay them off in. Snowball targets the smallest balance first so you clear whole debts quickly and build momentum. Avalanche targets the highest APR first so your extra money always goes to the most expensive debt. Everything else is identical: you pay every minimum, put whatever budget is left toward one target debt, and when a debt is paid off its minimum payment rolls forward onto the next.

Which method pays off debt faster?

With the same monthly budget, Avalanche always pays the same or less total interest than Snowball, and it often finishes a few months sooner. The difference grows when your highest-APR debt is also one of your largest. Sometimes the two tie. This calculator always shows both methods side by side, so you can see what the choice costs on your own numbers.

How does the payment rollover work?

Your monthly budget (every minimum payment plus your extra) stays constant for the whole plan. When a debt is paid off, you keep paying the same total each month: the freed-up minimum rolls onto the next target debt. That compounding rollover is what makes both methods work, and it’s why the last debts fall much faster than the first.

Why does the calculator say a debt “never clears at this payment”?

Because the monthly interest on that balance is at least as large as the money going toward it, so the balance holds steady or grows. For example, $5,000.00 at 36% APR adds $150.00 of interest in the first month, so a $100.00 payment can never catch up. Adding even a small extra amount per month, or negotiating the rate down, turns it around.

Is anything I type stored or sent anywhere?

No. The calculator runs in your browser. Your balances never leave this page, nothing is saved, and there’s no account or sign-up. Leave or refresh the page and the numbers are gone. The Debt Descent app works on the same principle: its App Privacy label is “Data Not Collected.”

Should I include my mortgage or student loans?

You can model any debt that has a balance, an APR, and a regular minimum payment. Many people run the Snowball or Avalanche method on high-interest consumer debt (cards, store cards, personal and car loans) and leave a long, low-rate mortgage out so it doesn’t dominate the timeline. Try it both ways and see which plan you’d follow.

What is Debt Descent?

Debt Descent is my native debt-payoff planner for iPhone, iPad, and Mac. It keeps your plan with you: log payments as you make them, watch your debt-free date move, and sync privately across your devices. One-time purchase, no subscription. Like this page, your data never leaves your devices.

More free tools

• Deferred Interest Calculator: what a “no interest if paid in full” promo bills if you miss the deadline.
• Balance Transfer Calculator: whether the transfer fee beats the interest you’d pay by staying put.
• Debt Management Plan Calculator: a DMP’s reduced rate and fees against paying on your own.

All of them run in your browser and send nothing back to me. They come from Debt Descent, my debt-payoff app for iPhone, iPad, and Mac. If you’re weighing it against another planner, I’ve written up Debt Descent vs Undebt.it and Debt Descent vs Debt Payoff Planner.