Debt Payoff Calculator — Snowball vs Avalanche
Add all your debts and see snowball and avalanche compared side by side — exact payoff order, total interest, and your real debt-free date for both strategies at once. Free, instant, any currency.
Snowball vs Avalanche — Compared Side by Side
Both strategies work the same way mechanically: pay the minimum on every debt, then throw all extra money at one target debt. When that debt is cleared, its payment rolls into the next target. The only difference is which debt you target first — and this calculator runs both simultaneously so you can see the real numbers for your specific debts, not just the general theory.
| Method | Targets First | Best For |
|---|---|---|
| ⛰️ Avalanche | Highest interest rate | Minimising total interest paid — the mathematically optimal choice |
| ⛄ Snowball | Smallest balance | Building early momentum — clears an entire debt fastest for motivation |
How the Calculation Works
Each month, every debt accrues interest based on its own APR, minimum payments are applied to all debts, and any extra payment goes entirely toward your current target debt (determined by whichever strategy you're comparing). Once a debt reaches zero, its former minimum payment amount gets added to your extra payment pool — this is the actual "snowball" or "avalanche" effect, where your payoff power grows as each debt clears.
Why Adding Debts Individually Matters
- Different debt types carry very different rates. Credit cards, personal loans, car finance and store cards often sit at wildly different APRs — lumping them together hides which one is actually costing you the most.
- The payoff order genuinely changes outcomes. A single high-rate credit card sitting untouched while you clear smaller, cheaper debts first can cost meaningfully more in total interest — this calculator shows you exactly how much.
- Named debts make the plan easier to follow. Naming each debt (rather than "Debt 1, Debt 2") makes your actual payoff order concrete and easier to stick to month after month.
Using Extra Payments Effectively
Every extra dollar you add above your minimum payments goes entirely toward your target debt under whichever method you're using — this is what accelerates payoff time dramatically compared to minimum payments alone. If you're not sure how much extra you can realistically commit, our Budget Calculator can help identify spare room in your monthly spending to redirect toward debt.
FAQs
What is the debt snowball method?
Pay off your smallest balance first while making minimum payments on everything else. Once cleared, roll that payment into the next smallest debt. Quick wins build motivation.
What is the debt avalanche method?
Target your highest interest rate debt first regardless of balance. This minimises total interest paid and is the mathematically optimal strategy, though it requires more patience since high-rate debts aren’t always small.
Which method should I actually use?
Avalanche saves more money mathematically. Snowball keeps more people motivated and on track. The best strategy is genuinely the one you’ll stick with until the last payment clears — many people start with snowball for momentum then switch to avalanche.
How many debts can I add?
Up to 10 debts, each with its own name, balance, interest rate and minimum payment.
What happens to a debt's minimum payment once it's paid off?
It gets added to your extra payment pool and rolled into your next target debt — this is what creates the accelerating “snowball” or “avalanche” effect.
How much extra should I pay each month?
Any amount helps significantly. Try different extra payment amounts to see the direct trade-off between payoff speed and total interest for your specific debts.
Does this account for a mortgage?
You can include a mortgage’s principal and interest portion if you want, but exclude the tax and insurance escrow portion, since only the actual debt paydown belongs in this calculation.
Is this calculator free?
Yes completely free with no sign-up needed.