Debt Payoff Calculator (Snowball vs Avalanche)

Enter each debt with its balance, rate and minimum payment, add whatever extra you can pay monthly, and compare the two classic strategies: snowball (smallest balance first, for motivation) versus avalanche (highest rate first, for maths).

Your debts

$
Best strategy for you —
❄️ Snowball smallest balance first
Debt-free in—
Total interest—
Payoff order—
⛰️ Avalanche highest APR first
Debt-free in—
Total interest—
Payoff order—
Avalanche saves—
⚠️—

Results update as you type and are estimates for education only — they don't account for taxes, fees or your personal situation, and nothing here is financial advice. Your inputs stay on this device.

How it works

  1. List every debt: balance, APR and minimum monthly payment.
  2. Set the extra amount you can put toward debt each month on top of the minimums.
  3. Snowball directs the extra at the smallest balance first; avalanche targets the highest interest rate first.
  4. When a debt is cleared, its payment rolls into the next target - the snowball effect both methods share.
  5. Compare months to debt-free and total interest paid under each method.

The formula

Each month, per debt: interest = balance x (APR / 12); balance = balance + interest - payment. The extra payment (plus freed-up minimums) goes to the current target debt until all balances reach zero.

Frequently asked questions

Snowball or avalanche - which should I choose?
Avalanche always costs the same or less in interest because it kills expensive debt first. Snowball wins on psychology: quick early victories keep people going. The calculator shows the exact interest difference for your debts - if it is small, pick snowball for the motivation; if it is large, the avalanche savings may be worth the patience.
Should I include my mortgage?
Usually no. These strategies are designed for consumer debt - cards, personal loans, car loans, overdrafts. Mortgages have low rates, long terms and sometimes overpayment limits, and including one makes the timeline less meaningful.
What if I can't pay more than the minimums?
Set extra payment to zero and the calculator still shows your debt-free date on minimums alone. Even a small extra amount - the price of one subscription - noticeably shortens the timeline, which you can verify by nudging the number.
Does missing the exact due dates change the result?
The model assumes one payment per debt per month, which is how most people budget. Real payoff dates can shift by a month or so with statement timing, but the comparison between methods - the part that drives the decision - stays accurate.
Keep planning

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