Evidence-first money workflow · Personal Money
Snowball Versus Avalanche Comparator
Compare snowball and avalanche payoff schedules using the same balances, APRs, minimums, monthly budget, rollover rules, and payoff evidence.
- 1Prepare
- 2Analyze
- 3Review and export
Prepare the evidence
Paste the documented CSV schema or choose a local CSV file. Nothing is sent to Nirmion.
Review the analysis
Summary metrics lead back to the rows that support them.
Method and interpretation
How to use Snowball Versus Avalanche Comparator
Use this comparator before selecting or revising a debt payoff order. Paid planners often show one debt-free date, but the decision is easier to inspect when both strategies use exactly the same balances, APRs, minimums, monthly budget, interest rounding, and start month. Nirmion calculates both paths and exposes the payoff order and monthly milestones behind the headline.
Prepare the input
List each unique debt with its current balance, nominal APR, and required minimum. Enter the total monthly amount available across all listed debts, including minimums and extra payment. The budget must cover initial minimums. Select one currency label and a YYYY-MM start month. Use zero APR when appropriate and exclude debts that should not share this payment pool.
Check the worked example
The example includes a high-rate store card, a larger lower-rate personal loan, and a credit-union card. With USD 650 per month, snowball attacks the smallest store-card balance while avalanche also favors it because it has the highest rate. Later ordering can differ, and the tables show when that difference affects interest or payoff month.
Read the evidence
Compare months, modeled payoff month, and total interest first. Then inspect per-debt payoff order and milestone tables. Snowball targets the smallest current positive balance. Avalanche targets the highest APR. Both roll a paid debt’s unused minimum and all remaining extra money to the next eligible debt in the same month. A small interest difference may coexist with a meaningfully different first payoff.
Calculation method
At the start of each modeled month, interest = opening balance × APR ÷ 12, rounded to the nearest minor unit. Required minimums are paid up to the amount due. Remaining budget follows the strategy order and rolls across debts until exhausted. The projection stops at payoff or 600 months; a plan that cannot amortize is blocked.
See CFPB’s explanation of how payment size affects card payoff time
Questions this workflow helps answer
Use these questions to confirm that this tool matches the task you need to complete.
- How do snowball and avalanche payoff schedules compare for the same debts?
- Which debt payoff strategy has the lower modeled interest and earlier payoff date?
- How does rolling freed minimum payments change snowball versus avalanche results?
Limits and decision boundary
The model assumes fixed APRs, fixed minimums, one monthly interest posting, no new charges, and on-time payments. Issuers may use daily balances and different minimum formulas. The comparison does not model promotions, deferred interest, taxes, fees, insurance, payment timing, or behavioral follow-through.
Common mistake
Do not enter extra cash as the monthly budget. The budget must include every minimum plus the extra amount, otherwise the result either fails validation or understates available payment.
Your pasted values and selected CSV files are processed in this browser tab. This workflow does not connect to a bank, save a budget, or provide financial, tax, legal, or investment advice.
Questions about this workflow
Does avalanche always show lower interest?
Under fixed rates and consistent execution it commonly does, but ties, minimums, rounding, and identical ordering can produce the same result. Real account terms can also differ from this model.
What happens after a debt is paid?
Any unused amount in that month rolls immediately to the next eligible debt, and later months retain the full portfolio budget until all debts reach zero.
Why is the payoff date modeled rather than guaranteed?
Future rates, fees, purchases, payment timing, minimum formulas, and missed payments are unknown. The date describes only the entered scenario.