Debt Snowball & Avalanche Calculator
Compare two ways of allocating one monthly budget across multiple debts. Snowball targets the smallest remaining balance; avalanche targets the highest APR. Both keep paying the entered minimums and roll freed payments into the next debt.
Your result
How the calculation works
Each month adds APR/12 interest, pays minimums, then allocates the remaining fixed budget by priority. Total budget = initial minimum payments + extra. Final payments are capped at the remaining balance; unused final-month cash is not charged.
Worked example
Two zero-interest debts of $100 and $200 with $50 minimums and $50 extra form a $150 monthly budget. Both strategies repay the $300 total in 2 months with no interest.
Assumptions and limitations
Minimums are fixed amounts, not percentages that shrink as balances fall. Interest is nominal monthly, with no new borrowing, fees or promotional changes. The projection stops with an error if it cannot repay within 100 years.
Check your contracts for minimums, daily interest, prepayment rules and promotional expiry. This calculator compares arithmetic, not credit suitability or debt advice.
Sources and editorial responsibility
Maintained by Renvoro Pty Ltd. Sources inform the methods and assumptions shown here; outputs have the limitations described on this page.
Method reviewed 2026-10-11. Calculation standards · Report an issue