Add all your debts and income sources to compare three payoff strategies side by side. See which approach saves the most interest and gets you debt-free fastest. The snowball method tackles the smallest balance first for quick wins, while the avalanche method targets the highest interest rate to minimize total cost.
When you have multiple debts, the question isn't just how much to pay each month — it's where to send the extra money first. The two best-known strategies are the snowball (smallest balance first) and the avalanche (highest interest rate first). Both work, but they answer different questions: avalanche minimizes total dollars paid, snowball maximizes early wins to keep motivation high.
This calculator lets you enter all your debts (credit cards, car loans, student loans, personal loans) along with their balances, minimum payments, and interest rates. It then projects three side-by-side scenarios: pay minimums only, run a snowball, and run an avalanche. You'll see total interest paid, months to debt-free, and a month-by-month timeline for each.
The math always favors avalanche — paying off high-rate debt first prevents the most interest from accruing. But research on actual consumer behavior, including studies in HBR and the Journal of Marketing Research, finds that people who use the snowball are more likely to stay with their plan to completion. The "best" method is the one you'll actually finish.
Three debts totaling $21,500, $540/month minimums, $200/month extra. Card A: $1,500 @ 22%, $40 min Card B: $8,000 @ 19%, $200 min Auto: $12,000 @ 6.5%, $300 min Avalanche (hit Card A first, then Card B, then Auto): Debt-free in: ≈ 34 months Total interest: ≈ $4,100 Minimum-only: Debt-free in: ≈ 78 months Total interest: ≈ $7,900 The extra $200/month saves $3,800 in interest and cuts payoff time by 44 months.
Same example, but a different lineup: Loan A: $500 @ 5% (a no-interest store card) Card B: $8,000 @ 24% (real problem) Auto: $12,000 @ 6.5% Extra: $200/month Snowball goes Loan A → Auto → Card B Avalanche goes Card B → Auto → Loan A Snowball pays off Loan A in month 2 (motivation!) but lets Card B accrue 24% for years. Avalanche keeps the small Loan A around but kills the 24% card much faster. Result: avalanche pays off the full lineup ≈ 4 months sooner and saves ≈ $1,500. Snowball still works — and if it keeps you on plan when you would have otherwise quit, it wins.
Use this calculator whenever you have more than one debt and any extra dollars to allocate. It's the right starting point for anyone wondering whether to consolidate, do a balance transfer, or just attack debts one at a time with what they have.
It assumes APRs stay constant. If you can lower a rate (negotiate with the lender, transfer to a 0% balance transfer card, refinance a personal loan), update the inputs to reflect the new rate. A rate reduction is often more impactful than any payoff-order optimization.
For single-debt cases (one credit card, one car loan), the simpler credit card payoff or auto loan calculators are easier to use. For students specifically, the student loan payoff calculator handles federal-loan-specific quirks like income-driven repayment.
Find out how long it will take to pay off your credit card and how much interest you will pay.
Plan your student loan payoff with standard and accelerated schedules.
Calculate your monthly car payment and total loan cost including trade-in and sales tax.
Calculate monthly payments, total interest, and effective APR for a personal loan.
Compare consolidating multiple debts into a single loan to see if you save money.
Generate a full amortization schedule for any loan.
Amount above all minimum payments to throw at debt each month
Total Debt
$45,000
Total Min Payments
$780
+ $200 extra
Best Strategy
Debt Snowball
Interest Saved (Best vs Worst)
$0
| Strategy | Months | Interest | Total Paid | Payoff Order |
|---|---|---|---|---|
| Debt SnowballBest | 4y 5mo | $6,732 | $51,732 | Credit Card → Car Loan → Student Loan |
| Debt Avalanche | 4y 5mo | $6,732 | $51,732 | Credit Card → Car Loan → Student Loan |
| Debt Mountain | 4y 5mo | $6,732 | $51,732 | Credit Card → Car Loan → Student Loan |
Debt Snowball
Pay off the smallest balance first, regardless of interest rate. When a debt is eliminated, roll its payment into the next smallest. This creates quick wins that keep you motivated — you see debts disappear fast, which builds momentum.
Debt Avalanche
Pay off the highest interest rate first, regardless of balance. This is mathematically optimal — it minimizes the total interest you pay over time. It may take longer to see your first debt eliminated, but you save the most money.
Debt Mountain CalcMountain Original
Pay off debts by their balance-to-interest ratio— targeting debts where you're paying the most interest relative to what you owe. A $5,000 debt at 22% costs more per dollar than a $25,000 debt at 5%. This hybrid approach often matches or beats the avalanche while providing faster early wins than pure interest-rate ordering.
Bottom line:The best strategy is the one you'll stick with. If you need motivation, use Snowball. If you want to minimize cost, use Avalanche. Debt Mountain offers a smart middle ground that considers both factors.