Reshape debt timelines with payment scenarios

How Credit Card Interest Destroys Wealth

Credit card interest rates typically range from 18–29% APR. At these rates, carrying a balance is one of the most expensive financial decisions you can make. Even adding 50/month to your minimum payment can save thousands and years of debt.

Why Minimum Payments Keep You Stuck

Minimum payments are designed to keep balances alive for as long as possible. It can help to think of them as a floor, not a target. Many people find that paying only the minimum on a 3,000 balance at 22% APR means years of repayments and a final interest bill that dwarfs the original debt. One approach is to treat any extra cash — a small bonus, a refund, a quieter month — as an opportunity to chip away faster. Even irregular overpayments make a meaningful difference over time. This is worth considering before dismissing small additional amounts as too insignificant to bother with.

The Mistake Most People Overlook

Many people focus entirely on the monthly payment figure and forget to check the APR. A lower minimum payment on a higher-rate card can actually cost more in the long run. Comparing the true cost of different repayment speeds — rather than just the monthly amount — gives a much clearer picture of where your money is actually going.

Quick example

With credit card balance of 3,000 and apr of 24 (plus minimum payment of 60 and extra payment of 100), the result is 24 mo. Change any figure and watch the output shift — it's often more useful to see the pattern than to memorise the formula.

Which inputs matter most

You enter Credit Card Balance, APR, Minimum Payment, and Extra Payment. Not every input has equal weight. Flip one at a time toward extreme values to feel which ones move the needle most for your situation.

What's happening under the hood

This calculator uses the standard amortization formula to project payoff timelines based on the balance, interest rate, and monthly payment. It assumes a constant APR with no additional fees, charges, or balance transfers. Results are estimates illustrating how payment amounts affect total interest paid and payoff duration. The formula is listed in full below. If the number looks off, you can retrace the calculation by hand — that's the point of showing the working.

Reading the output honestly

The payoff date assumes every payment lands on time and at the amount you entered. In reality, months with unexpected expenses happen. Treat the figure as the best-case timeline and add a buffer for life if you want a realistic target.

What this doesn't capture

Real payoff journeys include missed payments, fee changes, balance transfers, and promotional rates that reset. The calculation assumes a steady plan; reality is rarely that clean. Use the figure as the best-case plan against which actual progress gets measured.