Short answer: with the avalanche method (highest interest rate first) you almost always pay less interest; with the snowball method (smallest balance first) you get wins sooner, which helps many people stick with the plan. This calculator runs both methods on the same debts and the same monthly budget, side-by-side — same finish-line rules, so the difference you see is purely the payoff order. For the three example debts prefilled below ($12,700 total), both methods finish in 25 months, but the avalanche saves $93 of interest — and clears the expensive credit card two months earlier.
The same budget is used for both methods — minimums are always paid on every debt, and whatever is left over attacks one debt at a time. Clear a row’s balance to 0 to remove that debt.
| Debt-free date | — |
| Total interest | — |
| Debt-free date | — |
| Total interest | — |
Payoff order and interest per debt — Snowball
| Order | Debt | Paid off in | Interest paid |
|---|
Payoff order and interest per debt — Avalanche
| Order | Debt | Paid off in | Interest paid |
|---|
Educational estimate only — not financial advice. The simulation adds interest monthly at APR ÷ 12, pays each debt’s minimum, then puts the rest of your budget on one target debt (smallest balance for snowball, highest APR for avalanche). Real statements vary with payment dates and issuer rules. Your numbers never leave your browser.
How this calculator works
Enter each debt's balance, APR, and minimum payment, plus one number: the total you can put toward all debts each month. The simulation then repeats the same month for both methods:
- Interest is added to every balance (balance × APR ÷ 12).
- Every debt gets its minimum payment.
- Whatever budget is left over goes entirely to one target debt — the smallest balance (snowball) or the highest APR (avalanche). When that debt dies, its freed minimum joins the attack on the next one. That rollover is where the power comes from.
Because both methods use the identical budget and minimums, the comparison isolates the only thing that actually differs: the order. The per-debt breakdown under each method shows the payoff order, the month each debt dies, and how much interest that debt cost you under each plan.
Two honest warnings the tool also gives you live: if your budget is below the sum of minimums, it says so; and if a minimum payment doesn't cover a debt's monthly interest, that balance can never fall — the tool will show the plan as not finishing rather than inventing a date.
The worked example
Prefilled debts: a $1,200 store card at 19.99% APR ($35 minimum), a $4,500 credit card at 26.99% ($95 minimum), and a $7,000 personal loan at 11% ($140 minimum). Budget: $600 a month.
| Snowball | Avalanche | |
|---|---|---|
| Payoff order | Store card → Credit card → Personal loan | Credit card → Store card → Personal loan |
| First debt gone | Month 4 | Month 13 (store card follows month 15) |
| Debt-free | Month 25 | Month 25 |
| Total interest | $2,207 | $2,114 |
The avalanche's $93 edge here is small because the debts are similar in size. The gap widens when a large balance carries the highest rate: with an $800 loan at 6% and a $6,000 card at 26% on a $500 budget, snowball takes 17 months and $1,314 of interest; avalanche takes 16 months and $1,137 — a $177 saving. Run your own numbers; the honest answer is "whichever order you'll still be following in month six."
FAQs
Which method is actually better, snowball or avalanche? Mathematically, avalanche — it never pays a dollar of high-rate interest it could have avoided. Behaviorally, it's whichever keeps you going: the snowball's early wins are real motivation. This tool shows you the exact dollar cost of choosing motivation over math, so you can decide with open eyes.
Why do both methods take the same number of months in the example? Because the total budget is fixed. Order changes which balances shrink first, which changes interest — but with similar-sized debts the finish line often lands in the same month. The interest row is where the methods really differ.
What if I can only afford the minimums? Set your budget to the sum of the minimums and the tool shows the slow road honestly. Even $25 extra aimed at one target debt changes the result — try it and watch the interest total.
Does this include mortgages or auto loans? You can enter them, but this tool shines on revolving and installment consumer debt. Mortgages have their own dedicated payoff calculator (extra payments work differently over 30 years) — see the Mortgage Payoff Calculator.
Educational content only — not financial advice. The simulation is an estimate; actual payoff dates depend on statement cycles, payment posting dates, and issuer rules. Your numbers never leave your browser.
Sources: CFPB: how to reduce your debt (avalanche and snowball) Figures last verified Report a wrong number