You have three credit cards: $1,200 at 19% APR, $4,500 at 24% APR, and $800 at 15% APR. You can throw $400/month at debt beyond minimums. Should you attack the smallest balance first for quick wins, or target the 24% card to stop the bleeding? The debt snowball vs avalanche calculator answers this with your exact numbers.

Snowball ranks debts smallest to largest balance. You pay minimums everywhere, then dump extra cash on the smallest debt. When it's gone, roll that payment to the next smallest. The win? You eliminate debts fast, which keeps you motivated.

Avalanche ranks debts highest to lowest APR. Extra cash attacks the most expensive debt first. The math always favors avalanche—you stop high-interest charges earlier, so total interest drops. But it can take months to kill that first debt if it's large, and some people quit before they see progress.

This calculator compares both side by side using your actual balances, rates, and budget. You see exactly how much avalanche saves and how much faster snowball delivers that first payoff.

Choose avalanche if: Your debts have widely different APRs (e.g., one card at 24%, another at 8%). The interest gap makes avalanche savings significant—often $500-$2,000+ depending on balances. You're disciplined and don't need quick wins to stay on track.

Choose snowball if: You've tried debt payoff before and quit. Quick wins matter more than optimizing every dollar. Your debts have similar rates (18-22% range), so the interest difference is small anyway.

Consider a hybrid: Pay off one tiny debt first for momentum (snowball thinking), then switch to avalanche for the rest. You get the psychological boost without sacrificing much interest savings.

Run both strategies in this calculator. If avalanche saves less than $200 total, snowball's motivation might be worth more than the math.

Skipping the emergency fund: If you throw every dollar at debt but have zero savings, one car repair puts you right back on the credit card. Build $500-$1,000 in savings first, then attack debt aggressively.

Ignoring 0% promo rates that expire: A balance transfer at 0% seems low-priority for avalanche. But if it jumps to 26% in 6 months, you need to pay it off before expiration—or the math flips hard against you.

Still using the cards you're paying off: New charges accrue interest from day one when you carry a balance. Every $50 spent extends your timeline by weeks. Freeze the cards or cut them up.

Paying minimums only: Minimum payments are designed to keep you in debt. A $5,000 balance at 20% with $100 minimums takes 9+ years and costs $4,300 in interest. You need extra payments to make real progress.

Quitting after one setback: Life happens. If you skip an extra payment one month, don't abandon the plan. Get back on track next month. Progress isn't linear, but consistency wins.

The calculator uses standard monthly compounding. Each month, interest accrues on your balance:

For a $5,000 balance at 20% APR: $5,000 × 0.0167 = $83.33 interest per month

Payment allocation: Both strategies pay all minimums first. The remaining budget goes to the target debt (smallest balance for snowball, highest APR for avalanche). When a debt is paid off, its minimum rolls into the next target.

Assumptions: Fixed APRs throughout payoff, no new purchases, minimums calculated as percentage of balance (typically 1-3%) with a floor, and consistent monthly payments. Actual results vary if rates change, fees occur, or payments are missed.