Debt Payoff Calculator

About this tool

Carrying a balance on a credit card or personal loan can feel endless, because every month interest is added before your payment even lands. A debt payoff calculator cuts through that fog: it simulates your balance month by month, applying interest first and your payment second, until the balance hits zero.

Knowing your exact debt-free date changes behaviour. When you see that an extra $50 a month shaves off nine months and hundreds in interest, the trade-off becomes concrete instead of abstract. Use this tool to compare scenarios - your current minimum payment versus a fixed higher payment - and pick the plan you can actually stick to.

How to use

Enter your current balance owed, the annual interest rate (APR) printed on your statement, and the fixed amount you plan to pay each month. Press Calculate Payoff and the tool simulates every month for you.

The result shows three numbers: how many months until you are debt-free (with years for long payoffs), the total interest you will pay along the way, and the grand total leaving your pocket. Try raising the monthly payment to watch the interest collapse - that difference is the true cost of paying slowly.

The math behind it

Each month the interest charged is: balance x (APR / 12). Your payment first covers that interest; whatever is left reduces the balance. Months to payoff = ceil(-ln(1 - r x B / P) / ln(1 + r)), where r is the monthly rate, B the balance and P the payment.

This is why minimum payments are so expensive: when P barely exceeds the monthly interest, almost nothing touches the principal. Doubling the payment more than halves the total interest, because the balance - and therefore the interest - shrinks much faster.

Frequently asked questions

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