Debt Payoff Calculator
Snowball vs avalanche, side-by-side. Add your debts, set an extra payment, see exactly how much interest each strategy costs and how long it takes.
Your debts
Comparison
Snowball — smallest balance first
Months to debt-free
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Total interest
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Avalanche — highest APR first
Months to debt-free
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Total interest
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Which is better?
Mathematically, the avalanche always wins — it minimizes the interest you pay, because it kills the most expensive debt first. Behaviorally, the snowball often wins for real people, because clearing a small debt early creates momentum and reinforces the habit.
For someone with high-rate debt and discipline, avalanche is right. For someone who has tried and failed to pay off debt before, snowball is right. The "savings" of avalanche only matters if you actually stick with it.
How the calculator works
Each month: interest accrues on every debt at its APR, you pay the minimum on each, and the remaining "extra" budget goes entirely to one focus debt (smallest balance for snowball, highest APR for avalanche). When a debt is paid off, its minimum payment rolls into the extra budget — that's the actual "snowball" mechanism.
FAQ
What if I'm only making minimums?
Set "extra monthly payment" to $0. The strategies become identical (no extra to focus). You'll see total interest skyrocket — and that's the case for budgeting toward extra.
What about consolidation / balance transfer?
Not modeled here. A 0% APR balance transfer effectively pauses interest accrual for the promo period — replicate it by setting that debt's APR to 0.
Will paying off debt early hurt my credit score?
Briefly, yes — credit history length and credit mix can dip. But the score recovers quickly, and a paid-off debt is always a net positive.