Debt Avalanche Calculator NZ

This calculator applies the debt avalanche method to your debts in New Zealand, the payoff strategy that clears them with the least total interest. The idea is simple and ruthless: you pay the minimum on every debt to keep them all in order, then throw every spare dollar at the single debt charging the highest interest rate. Once that one is gone, you roll the whole payment, its old minimum plus your extra, onto the next-highest rate, and so on down the line, so the payment snowballs in size even as it targets the most expensive debt first. Because the highest-rate debt is doing the most damage, killing it first saves more interest than any other order. You enter up to three debts with their balance, interest rate and minimum payment, plus the extra amount you can put toward debt each month, and the calculator simulates the payoff month by month and shows how long until you are debt-free and the total interest you will pay along the way. Compare it with the snowball method, which targets the smallest balance first for motivation, to see the trade-off between maths and momentum. The key is to keep paying the same total every month and not take on new debt. Estimate only, not financial advice.

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Debt 1
$
%
$
Debt 2
$
%
$
Debt 3
$
%
$
$
3 yr 7 mo
until debt-free with the avalanche method
Total interest paid$5,641
Total monthly payment$610

Pays minimums on all debts, then all spare cash to the highest rate, rolling freed-up payments onward. Keep the total payment constant. Estimate only.

How it works

Each month the calculator adds interest to every debt, pays the minimum on each, then directs all remaining money to the debt with the highest interest rate. When a debt clears, its payment rolls onto the next-highest rate, so the total monthly payment stays the same. It repeats until every balance is zero, totalling the interest paid.

Worked example

With debts at 25, 19.95 and 12 percent and 200 dollars extra a month on top of the 410 dollars of minimums, the avalanche attacks the 25 percent store card first, then the 19.95 percent card, then the 12 percent loan, clearing the lot far sooner and for less interest than paying minimums alone.

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Frequently asked questions

What is the debt avalanche method?

You pay the minimum on every debt, then put all your spare cash toward the debt with the highest interest rate. When it is cleared, you roll that money onto the next-highest rate. It clears debt with the least total interest.

Is avalanche better than snowball?

The avalanche method saves the most interest and is usually fastest, because it kills your most expensive debt first. The snowball method targets the smallest balance first for quick wins and motivation. Avalanche wins on maths; snowball can win on willpower.

How do I make avalanche work?

Keep paying the same total amount every month even as debts clear, so the freed-up minimums roll onto the next debt. Avoid taking on new debt, and direct any extra cash to the highest-rate balance.