Number Debt Snowball Calculator
Two famous payoff plans, one honest race. Enter up to six debts and one monthly budget, and this calculator runs both the snowball (smallest balance first) and the avalanche (highest rate first) on the same numbers — months to debt-free and total interest, side by side.
The race — both plans on your numbers
| Plan | Debt-free in | Total interest | Payoff order |
|---|---|---|---|
| Run the race to see both plans. | |||
How it works
Each month, every debt accrues interest on its balance and receives its minimum payment. The rest of your fixed budget attacks a single target debt — the smallest balance in the snowball, the highest APR in the avalanche. When a debt dies, its minimum rolls into the attack money, so the payments snowball (or avalanche) bigger. The avalanche always wins on pure math; the snowball wins early victories, which is why many people stick with it longer.
Formula & worked example
Formula: Each month every debt accrues interest (balance × APR ÷ 12) and receives its minimum; the rest of the fixed budget attacks one target — the smallest balance (snowball) or the highest APR (avalanche). A cleared debt’s minimum rolls into the attack money, so payments grow as the list shrinks.
Worked example: Debts of $500 at 18% (minimum $25), $3,000 at 22% (minimum $60) and $8,000 at 8% (minimum $150), with a $400 monthly budget: both plans finish in 34 months. The snowball pays $1,747.70 of interest; the avalanche pays $1,726.54 — $21.16 less — while the snowball clears the $500 debt first for an early win.
When to use this
- You have several debts and keep paying whoever shouts loudest — you want one order and one budget instead.
- You have heard the snowball works because of motivation, not math, and want to see its exact price on your own debts.
- A small debt is nearly gone and you want to know how much bigger the attack gets when its minimum rolls over.
- You want the snowball and the avalanche raced on identical numbers before committing to either.
How to use it, step by step
- Add one row per debt (up to six): a name, the balance, the APR and its current minimum payment.
- Enter one total monthly budget that covers every minimum with something left over to attack with.
- Run the race and read the snowball row first: months, total interest and the payoff order.
- Check the first payoff month for the smallest debt — that early win is the snowball's whole argument.
- Compare the interest gap against the avalanche before deciding whether the motivation is worth the price.
What the inputs mean
| Input | What it is | Typical values |
|---|---|---|
| Balance (per debt) | What each debt currently owes, one row per debt | From a $200 store card to a five-figure loan |
| APR (per debt) | Each debt's own rate | Cards 18–30%; loans usually far lower — the spread drives the result |
| Minimum payment (per debt) | The dollar minimum you must pay monthly on each | Use the current statement figure |
| Total monthly budget | One fixed pot covering all minimums plus the attack money | Must at least equal the sum of the minimums |
Another worked example
Three debts — a $950 credit union loan at 9.5% (minimum $35), a $2,400 store card at 27.99% (minimum $70) and a $5,600 bank card at 18.5% (minimum $110) — paid from a $525 monthly budget. The snowball kills the credit union loan in month 3 and the store card in month 9, finishing everything in 21 months with $1,651.71 of interest. The avalanche on the same debts finishes in 20 months at $1,493.27, so on this stack the snowball's early wins carry a concrete price: $158.44.
Frequently asked questions
Snowball or avalanche — which is actually better?
On math, the avalanche: it never costs more interest, and often costs less. On the example debts here ($500 at 18%, $3,000 at 22%, $8,000 at 8%, $400 a month), both plans finish in 34 months — the avalanche pays $1,726.54 of interest against the snowball’s $1,747.70, a $21.16 edge. The snowball’s counter-argument is behavioral: clearing the $500 debt in the first few months keeps people going.
What budget should I enter?
Everything you can genuinely put toward these debts each month, minimums included. If the budget is below the sum of the minimums, no plan can work — the calculator will tell you the minimums alone need more.
Why do both plans take the same months but different interest?
The finish line is set mostly by the budget and the biggest debt, which both plans pay last here. The order of the smaller debts changes how much interest accrues along the way, not always how long the road is.
Can I include my mortgage or car loan?
You can, but payoff-plan math is designed for revolving and unsecured debts. Big secured loans have their own tools here — the Mortgage Payoff and Car Loan calculators model extra payments on those properly.
💳 One card at a time?
The Credit Card Payoff Calculator zooms in on a single balance — months to clear it and what the interest really costs.
My card minimum is a percentage of the balance, not a fixed amount. What do I enter?
Enter the dollar figure from your current statement. The catch is that a percentage minimum shrinks as the balance falls, so the simulation slowly overstates your minimums later on. Re-run the race every few months with fresh minimums and the picture stays honest — the order of debts rarely changes, even when the exact months move a little.
Will the plan still work if I keep using one of the cards?
No — the simulation assumes every balance only falls. New charges add principal and interest the plan never counted, and a card that keeps refilling can outrun the freed minimums rolling in behind it. The snowball only snowballs when the debts in the list are closed accounts in practice, even if they are technically still open.