Credit Card Calculator Online
Estimate how long it takes to pay off a credit card balance and how much interest you'll owe, calculated in your browser. Estimates only — not financial advice.
The Credit Card Calculator runs entirely in your browser. The balance, APR, and payment figures you enter never leave your device and nothing is uploaded to ArrayKit. Results are estimates only, not financial advice.
Open the Credit Card Payoff Calculator
About Credit Card Calculator
The Credit Card Calculator estimates how many months it will take to clear a card balance and how much interest you'll owe along the way, based on your balance, annual percentage rate (APR), and a fixed monthly payment. It simulates the balance shrinking month by month, so you can see the real cost of carrying a balance before you commit to a payment plan. If the payment you enter is too small to even cover a month's interest charge, the calculator warns you clearly instead of showing a misleading payoff date. It's useful for comparing payment amounts, planning a debt payoff, or simply understanding how APR compounds on a revolving balance. Everything runs locally in your browser — nothing about your balance or payment leaves your device — and the results are estimates only, not financial advice.
Features
- Estimates payoff time in months from a balance, APR, and fixed monthly payment
- Reports total interest charged and total amount paid over the payoff period
- Clearly warns when a payment is too small to ever clear the balance
- Handles a 0% APR as straight-line payoff with no interest
- Simulates interest compounding monthly on the remaining balance
- Copy a plain-text summary of the payoff time, interest, and total paid
- Instant results as you type, no page reloads
- Runs entirely in your browser with no balance or payment details sent anywhere
How to use the Credit Card Calculator
- Enter your current card balance
- Enter the card's annual percentage rate (APR)
- Enter the fixed amount you plan to pay every month
- Read the estimated payoff time, total interest, and total paid, or copy the summary
Example
Input
$3,000 @ 18% APR, $150/mo
Output
Payoff: 22 months
Interest: $278
Common errors & troubleshooting
- APR entered as a decimal like 0.18 instead of 18. — Enter the annual rate as a percentage — type 18 for 18% APR, not 0.18. The calculator treats the APR field as already-a-percent.
- Calculator warns the balance never pays off. — The monthly payment you entered is at or below the first month's interest charge, so the balance can never shrink. Raise the payment above the interest amount and try again.
- Payoff time looks shorter than a real statement shows. — The Credit Card Calculator assumes a fixed payment and a fixed APR every month. Real cards add fees, promotional-rate expirations, and new purchases that a static estimate can't account for.
- Total interest seems high for a small balance. — Credit card APRs compound monthly and are often much higher than loan rates, so even a modest balance can accrue significant interest if the monthly payment is close to the interest charge.
Frequently asked questions
- What does the Credit Card Calculator estimate?
- It estimates how many months it takes to pay off a credit card balance with a fixed monthly payment, plus the total interest and total amount you'll pay along the way, based on the balance and APR you enter.
- How does the Credit Card Calculator compute interest?
- Each simulated month it charges interest as balance × APR ÷ 12, subtracts your payment, and repeats until the balance reaches zero. This mirrors how most card issuers compute monthly interest on a revolving balance.
- Why does the Credit Card Calculator say my balance will never pay off?
- If your monthly payment doesn't exceed the interest charged that first month, the balance can't shrink — it would only grow. Increase the payment above the interest amount to see a real payoff estimate.
- Is the credit card interest calculator accurate for every card?
- It's a close approximation for a fixed APR and fixed monthly payment with no new charges. Real-world results can differ due to fees, promotional rates, grace periods, and any new purchases added to the balance.
- Does the Credit Card Calculator upload my balance or payment amount?
- No. The calculator runs entirely in your browser. The balance, APR, and payment you type never leave your device and are not uploaded to ArrayKit.
- Is the Credit Card Calculator financial advice?
- No — it produces estimates only, based on a simplified simulation. For a payoff plan tailored to your situation, talk to your card issuer or a financial advisor.
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