Debt Avalanche Calculator

Highest rate first, always

The avalanche orders debts by interest rate, ignoring balance. Minimums go to everything, and every spare pound attacks the highest rate until it clears. This is mathematically optimal: no other ordering pays less total interest or clears the debt faster, because each pound is always removing the most expensive borrowing available.

How much it actually saves

The gap against the snowball depends entirely on rate spread. With debts at 18, 19 and 20 percent, the two methods differ by very little. With a 24 percent card and a 4 percent student loan, the avalanche can save thousands and years. Running both orderings before choosing is worth the five minutes, because the answer is sometimes "it barely matters, pick the one you will stick to".

Why people abandon it

If the highest-rate debt also carries the largest balance, months can pass with no account closing. There is no visible win, and the plan feels like it is not working even while it is working better than the alternative. Knowing this in advance is the defence: tracking total interest saved rather than accounts closed gives the progress signal the method otherwise lacks.

Rate is not always the whole picture

A secured debt against your home or car carries consequences that an unsecured card does not, and a debt in collections or one about to lose a promotional rate may deserve priority over a nominally higher rate. Tax-deductible interest, where it applies, lowers the effective rate below the stated one. The avalanche ranks by cost, and cost is not always the same as the headline percentage.

Refinancing beats both methods

Before choosing an ordering, check whether the rate itself can be reduced — a balance transfer, a consolidation loan, or simply asking the issuer. Cutting a 24 percent rate to 12 percent does more than any payment ordering can, and it makes whichever method you choose finish sooner.

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