A debt payoff calculator lets you model two proven strategies — the snowball (smallest balance first) and the avalanche (highest interest rate first) — across all your debts at once. Enter each debt, set your extra monthly payment, and see exactly which method gets you debt-free faster and how much interest each approach costs.
Your Debts
This extra amount is thrown at your target debt on top of minimum payments for all debts.
Snowball
Smallest balance first
Avalanche
Highest interest rate first
Month-by-Month Timeline
| Month | Date | Payment | Interest | Remaining Balance | Event |
|---|
How to Use This Debt Payoff Calculator
The debt snowball and debt avalanche are the two most widely-used strategies for eliminating multiple debts. This debt payoff calculator simulates both month-by-month so you can see the exact difference in time, total interest, and payment sequence — then pick the approach that fits your personality and financial situation.
Step 1: Add All Your Debts
Click "Add Debt" for each debt you want to include — credit cards, personal loans, student loans, car loans, medical debt, or anything with a balance and an interest rate. For each debt, enter: a recognizable name (e.g., "Chase Visa"), the current outstanding balance, the annual percentage rate (APR), and the minimum required monthly payment. Your minimum payment is listed on your monthly statement. Include every debt you want to eliminate; the more complete your picture, the more accurate the comparison.
Step 2: Set Your Extra Monthly Payment
After all minimums are covered, how much extra can you put toward debt each month? This extra payment is the engine of both strategies — the calculator applies it to your current target debt on top of all minimums. Even $100–$200 extra per month can save thousands in interest and cut years off your payoff timeline. If you are not sure, start with whatever feels comfortable and use the results to motivate you to find more.
Step 3: Click "Compare Strategies"
The calculator runs two simultaneous month-by-month simulations. In the snowball simulation, extra funds go to the lowest-balance debt first. In the avalanche simulation, extra funds go to the highest-APR debt first. When a debt is fully paid off, its minimum payment is automatically rolled into the next target debt — amplifying your payoff speed over time.
Step 4: Review the Side-by-Side Results
The two strategy cards show you months to debt-free, total interest paid, debt-free date, and the exact order in which each debt gets eliminated. The banner below highlights which method wins on interest savings — it is almost always the avalanche — and how large the gap is. If the difference is small, you may prefer the snowball for its motivational quick wins. If the difference is large, the avalanche saves meaningful money worth the extra patience.
Step 5: Study the Month-by-Month Timeline
Toggle between the snowball and avalanche views to see every payment month — total paid, interest charged, remaining balance, and any payoff events. Watching individual debts disappear on the timeline is one of the most motivating outputs of this debt payoff calculator. Everything runs in your browser; no data leaves your device.
For a detailed walkthrough, see our guide: Debt Avalanche vs Snowball Method.
FAQ
Is this debt payoff calculator free?
Yes, this debt payoff calculator is completely free with no hidden fees, no signup, and no limits. You can add as many debts as you like, run snowball vs avalanche comparisons, and view full month-by-month schedules at no cost. Everything runs locally in your browser.
Is my financial data private?
Absolutely. All calculations run entirely in your browser using client-side JavaScript. Your debt balances, APRs, and payment details are never sent to any server or stored anywhere. You can disconnect from the internet and the calculator will keep working perfectly.
What is the debt snowball method?
The debt snowball method, popularized by Dave Ramsey, involves paying the minimum on all debts and directing any extra money toward the debt with the smallest balance. Once that debt is paid off, you roll that payment into the next smallest balance. This approach provides quick psychological wins and helps build momentum.
What is the debt avalanche method?
The debt avalanche method directs extra payments toward the debt with the highest annual percentage rate (APR) first, regardless of balance size. Once the highest-rate debt is eliminated, you move to the next highest rate. This approach minimizes total interest paid and is mathematically optimal.
Which method is better — snowball or avalanche?
The avalanche method almost always saves more money in total interest paid. However, the snowball method's quick wins can provide powerful motivation that keeps people on track. Research shows that the debt snowball leads to better completion rates for some people. The best method is the one you will actually stick to.
How much extra payment should I put toward debt?
Any extra amount helps. Even an additional $25–$50 per month can cut months off your payoff timeline and save hundreds in interest. A commonly recommended target is to put at least 20% of your take-home pay toward debt beyond minimums. Use the calculator to see exactly how different extra payment amounts affect your debt-free date.
What happens to my minimum payments after a debt is paid off?
Both strategies 'roll' the freed-up payment into the next target debt. For example, if you were paying $150/month minimum on a card you just paid off, that $150 gets added to your payment on the next target debt. This is what creates the 'snowball' or 'avalanche' acceleration — your total monthly payment stays the same but goes entirely to fewer and fewer debts.
Can I add more than two debts?
Yes, you can add as many debts as you like — credit cards, personal loans, student loans, auto loans, or any other installment debt. The calculator will simulate month-by-month payoff for all of them simultaneously under both the snowball and avalanche strategies and show you the full payment order for each.