Compare snowball vs avalanche across all your debts — and see the exact month you become debt-free.
Estimates assume fixed monthly payments, monthly compounding, and no new charges. Issuers calculate minimums as a percentage of the balance and may add fees or change variable APRs. This is educational, not financial advice.
Paying $975 a month clears everything in 3 yr 5 mo. That is 4 yr 2 mo sooner and $4,897 less interest than paying only the minimums.
| # | Debt | Balance | APR | Interest | Paid off |
|---|---|---|---|---|---|
| 1 | Credit card | $6,200 | 24.99% | $1,455 | Jul 2028 |
| 2 | Personal loan | $4,800 | 12.50% | $839 | Nov 2028 |
| 3 | Car loan | $9,400 | 7.50% | $1,187 | May 2029 |
| 4 | Student loan | $14,000 | 5.50% | $1,943 | Mar 2030 |
Snowball attacks the smallest balance first for an early win. Avalanche attacks the highest APR first for the lowest total interest. Both keep your total monthly outlay constant and roll freed-up minimums into the next debt.
Each month, interest is charged on every remaining balance, minimums are paid on all debts, and whatever is left of the fixed budget attacks the priority debt. When a debt closes, its minimum joins the attack on the next one.
Priya has a $6,000 card at 24% ($150 minimum) and a $3,000 personal loan at 6% ($100 minimum). She can add $150 a month, so her total budget is $400.
| Lever | Effect | How to use it |
|---|---|---|
| Extra monthly payment | Straight to principal on the target debt | Even $50–$100 shortens the schedule; keep it sustainable. |
| Highest APR | Largest interest cost per dollar owed | Avalanche attacks it first; avoid letting a 25%+ card sit behind a low-rate loan. |
| Small balance | Fastest account closure and motivation | Snowball clears it first, then rolls the minimum forward. |
| New charges | Adds principal and can restart the clock | Stop using the cards you are paying off, or the plan breaks. |
| One-time windfall | Cuts months immediately | Apply it to the target debt, not spread thin across all balances. |
While the snowball and avalanche order differ, the mechanics are identical once you have a fixed budget: minimums everywhere, everything else on one target.
Compare snowball vs avalanche across all your debts. Add an extra payment and see your debt-free date, interest saved, and payoff order. Free and private.
The Debt Payoff Calculator turns a pile of balances into a dated plan. Enter each debt — a name, current balance, APR, and minimum payment — then choose snowball or avalanche and an extra amount you can add each month. The tool simulates every month until the last balance reaches zero and returns the month you become debt-free, the total interest you will pay, how much interest and time you save compared with paying only minimums, the order each account is cleared, and a balance-over-time chart that puts both strategies on the same axis. The sample plan carries four debts totalling $34,400 at rates from 5.5% to 24.99%, a realistic mix of card, personal, auto, and student debt. Everything runs locally in your browser; no balances are uploaded or stored on a server.
The engine uses the standard fixed-budget payoff model. Each month begins by charging interest on every remaining balance at APR ÷ 12. It then pays the minimum on each debt and applies whatever is left of the monthly budget to the target — the smallest balance for snowball or the highest APR for avalanche. When a target is cleared, the leftover budget and the freed minimum roll to the next debt, so the total outlay stays constant while the attack gets larger. The comparison baseline pays only the minimums on each open debt and lets the outlay shrink as accounts close. The simulation caps at 50 years and flags any plan that still has a balance at that point, which usually means a minimum is below the monthly interest or the budget is too small to amortize the debt.
Avalanche is the cheaper method by construction: every extra dollar goes to the balance accruing the highest rate, so total interest is minimized. Snowball can cost more, but it closes an account sooner, which many people find motivating enough to stay consistent — and consistency is what actually pays off debt. The gap between the two depends on how spread out your rates are. With one 24.99% card and several loans under 8%, avalanche usually wins clearly; when every rate sits within a few points, the difference may be a few hundred dollars and the behavioral edge of snowball can be worth more than the math. A sensible default is to start with avalanche, switch to snowball if you need early wins, and never let the decision delay the first extra payment. The strategy buttons update the entire plan instantly, so you can compare before committing.
The levers are simple: pay more, pay less interest, and stop adding principal. An extra $50–$100 a month compounds into months saved because it attacks principal directly, and a one-time windfall should go to the target debt rather than being spread thin. New charges are the silent plan-killer: a single new balance at a high APR can undo months of progress, so remove the cards you are paying off from your wallet or freeze them. Before accelerating, keep a small emergency buffer so an unexpected bill does not force you back onto the cards; a $1,000 cushion prevents more damage than an extra $1,000 of payoff usually creates. Balance transfers can lower the rate, but only if the fee is low relative to the interest saved and the balance clears before the promotional period ends. If the plan still does not fit, a nonprofit credit counselor can negotiate a structured repayment plan; this calculator is an educational model, not financial advice.
Both methods pay minimums on every debt and put all spare money toward one target. The snowball targets the smallest balance first, so accounts close quickly and momentum builds. The avalanche targets the highest interest rate first, so you pay the least total interest. Snowball is a motivation strategy; avalanche is a math strategy. This calculator runs both side by side so you can see the actual difference in your payoff date and total interest.
If one balance charges a much higher APR — typically a credit card above 20% — avalanche usually saves the most money and wins by a wide enough margin to justify it. If your rates are similar, or you have struggled to stay motivated, snowball’s early wins may be worth a small interest premium. The tool labels the cheapest and fastest plan for your exact numbers, which is more useful than a blanket rule.
Each month it charges interest on every balance, pays every minimum, and puts the rest of your fixed monthly budget toward the target debt. When a debt is cleared, its minimum payment does not disappear from the budget — it rolls into the attack on the next debt. That rollover is why the payoff accelerates even if your extra payment never changes.
Issuers often quote a minimum-payment estimate based on a percentage of the balance, and minimums fall as the balance falls, which stretches payoff far into the future. This calculator holds your entered minimum fixed, assumes no new charges, and ignores fees, variable-rate changes, and promotional APR cliffs. Use it as a planning model, then check your statement for the issuer’s current minimum formula.
The balance is negatively amortizing: it grows even when you pay on time. You will see a warning on any debt where the minimum is at or below balance × APR ÷ 12. That debt needs more than the minimum — either make it the payoff target or increase your total monthly budget — otherwise no ordering strategy will clear it.
Paying down revolving balances usually helps, because credit utilization is a large scoring factor. Closing the account is different: it can reduce available credit and shorten your average account age. If there is no annual fee, many people keep the oldest card open with a small recurring charge paid in full. The calculator models payoff, not credit scoring — check your issuer’s terms before closing anything.
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