How to use this debt payoff calculator
Grab your latest statements. For each debt, enter the current balance, the APR (the yearly interest rate, not the monthly one), and the minimum payment the lender asks for. Then enter how much you can pay each month on top of all those minimums. Even $50 changes the picture more than most people expect.
The calculator runs the same debts through two payoff orders at once. Each month it adds interest, pays every minimum, and sends the extra to one target debt. When that debt hits zero, its minimum joins the extra and the bigger payment moves to the next debt. That roll-forward is what makes both methods work, and it's why sticking with the same total payment matters more than the order you pick.
Debt snowball: smallest balance first
The snowball method lines your debts up from the smallest balance to the largest, regardless of interest rate. You throw everything extra at the smallest one. The first payoff often comes within a few months, and that early win is the point. Seeing one account go to $0 makes it easier to keep going when the bigger balances feel endless.
The trade-off is cost. If your smallest balance has a low rate and a big card has a high one, snowball lets that expensive card keep charging interest longer. The calculator shows exactly how much that costs you in dollars, so you can decide whether the motivation is worth it.
Debt avalanche: highest interest rate first
The avalanche method sorts debts by APR, highest first, and aims the extra money there. Mathematically, this is the cheapest order. Every extra dollar goes where it's costing you the most, so total interest is the same or lower than snowball, and you're usually debt-free a little sooner.
The catch is patience. If your highest-rate debt is also your biggest, it can take a long time before anything disappears from the list. Some people find that hard to stick with, and a plan you abandon in month four saves nothing.
Which one should you pick?
Look at the interest difference in the results. If avalanche saves only a few dollars, or the payoff order is nearly the same either way, go with snowball and enjoy the quick wins. If avalanche saves hundreds or more, it's probably worth the wait, especially on high-rate credit cards. A middle path works too: knock out one tiny balance first for momentum, then switch to avalanche.
Whichever you choose, the biggest lever is the extra payment itself. Try a few amounts in the calculator and watch the debt-free date move. If you can't find extra money yet, start with how to create a budget when money is tight, and keep a small emergency fund so one car repair doesn't land back on a card.
What this calculator doesn't include
Results are estimates. Interest is figured monthly on each balance and rounded to the cent. Real lenders may compound daily, charge fees, change variable rates, or lower your minimum as the balance falls, so your actual dates can differ by a month or two. It also doesn't model 0% balance transfer promos or new charges. If you're still using a card, the payoff date will slip.
For a deeper walk-through with a worked example, read Debt Avalanche vs Snowball: Which Payoff Method Saves More?. If you'd rather track progress on paper, print the free Debt Snowball Tracker or browse all the free budget printables. More guides are in the debt management section.
Debt payoff calculator FAQ
Is the debt snowball or avalanche method better?
Avalanche, which pays the highest APR first, always costs the same or less in interest. Snowball, which pays the smallest balance first, gives you faster early wins. If the interest gap in the calculator is small, choose the one you're more likely to stick with.
What counts as the extra monthly payment?
It's whatever you can pay on top of all your minimums combined. If your minimums add up to $405 and you can afford $605 a month toward debt, enter $200. When a debt is paid off, its minimum rolls into the extra automatically.
Should I include my mortgage or student loans?
You can include any fixed-rate debt. Many people leave out the mortgage because it runs for decades at a low rate and would push the payoff date far out. Federal student loans on an income-driven plan don't fit a fixed minimum well, so treat the result as a rough guide for those.
Why does the calculator say a debt won't be paid off?
If the payments you enter don't cover the monthly interest, the balance never shrinks. Raise the minimum or the extra payment until the warning goes away. On a credit card, the real minimum usually covers at least the interest plus about 1% of the balance.
Is my information saved anywhere?
No. The calculator runs entirely in your browser. Nothing you type is stored or sent to SaveNests, and it clears when you close the page.
Educational estimates only, not financial advice. Check your lender's statements for exact figures.