Tiny Toolkit

Credit Card Interest Calculator

Enter your credit card balance and APR to see how long it takes to pay off and how much interest you'll pay in total. Compare a fixed monthly payment against the minimum-payment trap — which can extend repayment by years and multiply the interest cost. All calculations run client-side.

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Frequently Asked Questions

Why does it take so long to pay off with minimum payments?
Minimum payments are typically 1–3% of your balance. Early on, most of the payment goes to interest, so your balance falls very slowly. As the balance drops, so does the minimum payment, extending the repayment even further.
How is the monthly interest rate calculated?
Your APR (Annual Percentage Rate) is divided by 12 to get the monthly rate. For a 24.99% APR, the monthly rate is about 2.08%, charged on your remaining balance each billing cycle.
What's the fastest way to pay off credit card debt?
Pay more than the minimum every month. Even an extra $50–$100 per month can shave years off the repayment and save hundreds in interest. The avalanche method (targeting highest-APR cards first) is the most mathematically optimal approach.

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