Debt Snowball Calculator 2026
You're paying thousands in unnecessary interest. See snowball vs avalanche side-by-side — with the exact payoff date for each.
How to Use This Calculator
Tab "Snowball vs Avalanche"
Enter your debts — name, balance, APR, and minimum payment for each. Add up to 15 debts using the "Add debt" button or quick-start templates. Set your extra monthly payment (on top of all minimums). The calculator runs both strategies side-by-side: Snowball (smallest balance first) and Avalanche (highest APR first). See the exact difference in interest paid, months to debt-free, and which debt disappears first under each method.
Tab "Debt-Free Date"
Set a target date (in months) and pick your strategy. The calculator works backwards to find exactly how much extra you need to pay each month to be debt-free by that date. It also shows what happens if you make only minimum payments — so you can see the cost of waiting.
Tab "Consolidation Check"
Enter a consolidation loan's APR, term, and origination fee. The calculator compares your current debts (paid via avalanche at minimum payments) against a single consolidation loan — side-by-side. It gives a clear verdict: green (save money), yellow (trade-off), or red (costs more).
The Formulas
Interest = Balance × (APR / 12)
New Balance = Balance + Interest − Payment
Snowball Sort: debts sorted by balance ascending (smallest first)
Avalanche Sort: debts sorted by APR descending (highest first)
Freed-Payment Cascade:
When a debt is paid off, its minimum payment is added to the extra payment pool.
This "snowball" of freed payments accelerates payoff of remaining debts.
Consolidation Loan (standard amortization):
Loan Principal = Total Balance + Origination Fee
PMT = P × r(1+r)n / ((1+r)n − 1)
where r = APR/12, n = term in months
Total Paid = PMT × n
Total Interest = Total Paid − Original Balance
(Origination fee is baked into the loan principal — not added separately to total cost)
Reverse Solve (Debt-Free Date):
Binary search for the extra payment that achieves target months.
60 iterations, precision within $1.
Example
Sarah — Marketing Manager in Texas
4 debts totaling $38,000. Extra payment: $300/month.
With snowball, Sarah's credit card is gone in 9 months — a quick win. With avalanche, it's also first (highest rate), but the math saves her $660. If she consolidates at 9.5% over 48 months, she'd pay $4,100 in interest — but her monthly payment drops by $180. Trade-off: lower payment vs. 15 extra months.