🏔️ Debt Avalanche Payoff Calculator

Add your debts with balance, interest rate, and minimum payment, plus any extra you can pay each month. The avalanche method directs your extra payment toward the highest interest rate first to minimize total interest paid.

What the month-by-month loop does

Every debt steps forward a month at a time. The debt with the highest APR still outstanding takes the whole extra payment; the rest get their minimum only:

interest = balance x (APR / 100 / 12)
balance  = balance + interest - payment
payment  = minimum + (extra if this is the highest-rate debt)

The sample list - $1,000 at 22%, $5,000 at 6%, $2,000 at 25% - with $200 extra clears in 24 months for $784.67 of interest. The 25% card goes first and is gone in month 9, the 22% card in month 14, the car loan last.

Avalanche against snowball, on these same debts

Avalanche pays the highest rate first and is the mathematically cheaper order. Snowball pays the smallest balance first and wins on motivation, because the first debt disappears sooner. Feed this list to the snowball and the $1,000 card clears in month 5 instead of 9, but the total interest is $836.16 - about $51 more over the same 24 months. The gap widens with the spread between your rates and with how long the debts run.

When a debt is cleared here, its minimum payment is not rolled into the next debt - only the extra moves along. Redirect that freed minimum yourself and the same list finishes in 21 months for $753, so treat the timeline as the cautious version.

Frequently asked questions

Is the debt avalanche actually cheaper than the snowball?

Yes, by construction - paying the highest rate first always costs the least interest. On the sample debts it saves $51.49 over two years, more when a high-rate card also carries a large balance.

Should I still use the avalanche if the snowball feels better?

Run both and compare. When the gap is small, as it is here, the order you will actually stick to wins.

Why does it say 50+ years?

The simulation stops after 600 months. That happens when a minimum payment is smaller than the monthly interest on its own balance, so that debt grows no matter what the others do.