Debt Payoff Calculator
Enter your credit cards, loans, and other debts to see your debt-free date, total interest paid, and the exact order to pay them off, using either the avalanche or snowball method.
Your debt-free date will appear here
Enter your debts and minimum payments, then click calculate.
Quick Answer
A debt payoff calculator shows how long it will take to become debt-free and how much interest you'll pay, based on your balances, interest rates, and minimum payments. It compares the avalanche method, which targets the highest interest rate first, against the snowball method, which targets the smallest balance first.
How It Works: Formula & Variables
Balance = Balance + (Balance × APR ÷ 12) − Payment
- Balance
- The remaining amount owed on a debt, updated each month.
- APR
- The annual interest rate on the debt, divided by 12 for the monthly rate.
- Payment
- The minimum payment on every debt, plus any extra payment directed at the current target debt.
Each month, every debt accrues interest and receives at least its minimum payment. Any extra amount, plus the minimum payments freed up from debts already paid off, goes toward the target debt: the highest APR under avalanche, or the smallest balance under snowball.
Worked Examples
Example 1: Avalanche on two cards
A $6,000 balance at 24% APR ($150 minimum) and a $3,000 balance at 12% APR ($90 minimum), with $200 extra a month, put the full extra toward the 24% card first under avalanche. That card clears in a little over 2 years, then its $150 minimum rolls into the second card, which is paid off shortly after. The total interest ends up meaningfully lower than if you'd split payments evenly between the two.
Example 2: Snowball for quick wins
The same two debts under snowball put the $200 extra toward the $3,000 balance first, since it's the smaller one, even though its rate is lower. It gets knocked out faster, freeing up its $90 minimum plus the extra to attack the $6,000 balance next. That's a quicker first win, though it costs a bit more in interest over the full payoff.
Key Concepts
Avalanche minimizes total interest: Because it always targets the highest APR, avalanche is mathematically the cheapest way to pay off multiple debts, assuming you stick with the plan.
Snowball builds momentum: Paying off smaller debts first gives you visible wins sooner, which research on behavior change suggests helps some people stay consistent, even though it can cost slightly more in interest.
The "snowball effect" applies to both methods: Whichever strategy you pick, once a debt is paid off, its minimum payment gets redirected to the next target debt, so your payoff speed increases over time even without adding new money.
Common Mistakes
Only making minimum payments: Minimum payments are calculated to keep a debt current, not to pay it off quickly. Most of the payment goes to interest, especially on high-APR cards.
Spreading extra payments across every debt evenly: Splitting extra money across all debts feels fair, but it takes longer and costs more in interest than concentrating it on one target debt at a time.
Forgetting to redirect payments after a debt is paid off: If you don't roll a cleared debt's minimum payment into your next target, you lose the acceleration that makes both the avalanche and snowball methods work.
Frequently Asked Questions
The avalanche method puts every extra dollar toward the debt with the highest interest rate first, which minimizes the total interest you pay over time. The snowball method instead targets the smallest balance first, which pays off individual debts faster and can help you stay motivated, even if it costs a bit more in interest overall.
Avalanche saves you the most money if you stick with it, since it always attacks the highest-rate debt. Snowball tends to work better for people who need quick wins to stay on track, since crossing a debt off the list entirely feels more motivating than watching a big balance shrink slowly. Try both in the calculator and see which timeline and payoff order feels more realistic for you.
Once a debt is fully paid off, its minimum payment doesn't disappear. It gets rolled into the extra payment going toward your next target debt. That's why your payoff accelerates over time: each debt you eliminate frees up more money to throw at the next one.
Your APR determines how much interest builds up on the balance every month, which is what the avalanche method uses to decide the payoff order. A card with a 24% APR compounds much faster than a loan at 7%, so it usually makes sense to attack the high-rate balance first even if it isn't the largest one.
Yes. Even a modest extra payment can cut months or years off your payoff timeline, because it goes straight toward reducing the balance that interest is calculated on. Try a few different amounts in the calculator and watch how much your debt-free date and total interest paid shift.