Financial Calculators
Debt Snowball & Avalanche Calculator
Compare debt snowball and debt avalanche strategies using balances, APRs, minimum payments and one extra monthly amount across up to 20 debts.
Compare debt payoff strategies
Debt Snowball & Avalanche Calculator
Compare two fixed-rate debt payoff strategies with a constant monthly payment budget and no saved financial data.
Planning results
How this calculator works
Each month starts with interest = opening balance × APR ÷ 12. Fixed entered minimums are applied, capped at the amount owed. The initial sum of minimums plus extra stays the monthly budget: freed minimums and unused final-payment amounts roll to the next target immediately. Snowball uses the initial lowest balance first; avalanche uses the highest APR first. Ties keep input order. Non-target debts may be paid off through their minimums earlier than the planned target order. Rates and minimums stay fixed; promotional rates, fees, and daily issuer compounding are not modeled. Balances may temporarily grow if minimums do not cover interest; results flag this. A 1,200-month bound and no-progress checks prevent endless simulations. Comparisons apply only to the entered assumptions.
Results are estimates for planning purposes only and do not constitute financial, investment, tax, lending, or legal advice.
Your calculation is processed in your browser and is not stored by this tool.
Results are estimates and do not change creditor terms. Check statements, fees, minimum-payment rules and payment allocation with each creditor.
How to use the debt payoff calculator
- 1
Add each debt name, current balance, annual percentage rate and required minimum payment.
- 2
Enter the extra amount you can apply every month.
- 3
Calculate both strategies using the same total monthly payment budget.
- 4
Compare payoff months, estimated interest and repayment order.
- 5
Review the schedule and confirm the plan against current creditor statements.
Debt snowball versus debt avalanche
The snowball method targets the smallest starting balance first while paying required minimums on the other debts. The avalanche method targets the highest APR first. When a debt is cleared, its former payment rolls into the next target, so the modeled total monthly debt budget stays constant until all balances are repaid.
Avalanche often reduces mathematical interest cost because it attacks the most expensive rate first. Snowball can create an earlier small-balance payoff, which some people find motivating. The calculator shows both results; it does not decide which behavior is sustainable for you.
Debt payoff example
Consider three debts: $3,000 at 5% with a $100 minimum, $5,000 at 20% with a $150 minimum, and $10,000 at 8% with a $250 minimum. Add $300 extra, creating an $800 monthly budget. In the model, both strategies finish in about 25 months, but avalanche saves about $363 in interest.
Snowball starts with the $3,000 balance. Avalanche starts with the 20% APR balance. Actual statement interest and payoff timing may differ.
How extra payments are applied
Every debt receives its required minimum where possible, and remaining budget goes to the current target. If a target is paid off during a month, unused money can move to the next debt. The model assumes payments happen monthly and that no new charges are added.
Important warnings and limitations
- Negative amortization: if a minimum payment does not cover monthly interest, the balance may grow; the tool warns when payoff is not supported.
- Creditor rules: fees, promotional rates, changing minimums and payment-allocation policies can alter results.
- No new borrowing: additional purchases, cash advances and missed payments are excluded.
- Fixed budget: the model keeps the starting minimum-payment total plus extra payment available.
- Get help when needed: contact creditors or a qualified nonprofit counsellor if required payments are unaffordable.
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Debt Snowball & Avalanche Calculator FAQ
What is the debt snowball method?
It directs extra money to the smallest starting balance while maintaining other required payments.
What is the debt avalanche method?
It directs extra money to the highest APR first to reduce interest mathematically.
Which method saves more interest?
Avalanche often does, but the exact result depends on balances, rates and payments.
Can I include extra monthly payments?
Yes. The extra amount is added to the starting total of minimum payments.
What happens after one debt is paid?
Its available payment rolls to the next target in the modeled order.
Why might the calculator show a payoff warning?
A minimum may be too low to cover interest, or the entered payment budget may not support payoff.
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