The formula
How it works
See how long it will take to clear a credit card balance at a fixed monthly payment, and how much interest you will pay along the way. A small increase in the payment can dramatically shorten the time.
FAQ
Why does my card take so long to pay off?
Credit card interest rates are high, so a large slice of each payment goes to interest rather than the balance. If your payment barely exceeds the monthly interest, the debt shrinks painfully slowly.
What if my payment is too low?
If the monthly payment does not cover the interest charged, the balance never falls — it grows. The calculator flags this, because no fixed payment below the interest can ever clear the card.
Does paying a little extra each month really help?
Yes — because interest is charged on the shrinking balance, even a modest extra amount goes straight toward principal and compounds into a shorter payoff time and less total interest.
Is this different from paying only the minimum?
Card issuers usually set the minimum payment low on purpose, often around 1–3% of the balance, which stretches payoff over many years. Entering a fixed payment well above that minimum here shows how much time and interest you can save.
How does a balance transfer or 0% APR offer change the math?
Set the APR to 0 (or the promotional rate) to see how fast the same monthly payment would clear the balance without interest working against you — a useful comparison before transferring a balance.
What if I have several cards to pay off?
Run each card through the calculator separately with its own balance, APR and payment to see which clears fastest, then decide whether to attack the highest-rate card first or the smallest balance first.
Is the interest calculated daily or monthly?
This calculator compounds interest once a month using the APR divided by 12, which closely matches how most issuers bill, though a few compound daily and may charge slightly more.
About the credit card payoff calculator
This calculator shows how many months it will take to pay off a credit card if you make a fixed payment each month, and the total interest you will hand over in the process. Credit cards charge some of the highest interest rates around, and paying only a little each month can stretch a modest balance into years of debt. Putting a number on the timeline and the interest makes the cost of carrying a balance impossible to ignore.
How to use it
Enter your current card balance, the card’s APR, and the fixed amount you plan to pay each month. The calculator returns how long it takes to reach a zero balance and the total interest paid. For example, a $5,000 balance at 18% APR paid off at $200 a month takes about 32 months and costs roughly $1,300 in interest. Try raising the monthly payment to see how quickly the payoff time drops.
The formula
The number of months is , where is the balance, is the monthly rate (APR divided by 12) and is the monthly payment. The term is the first month’s interest; if the payment is not bigger than that, the logarithm is undefined and the balance never clears. Total interest is the sum of all payments minus the original balance.
Where it is used
People use it to make a plan for getting out of credit card debt, and to see the payoff for paying more than the minimum. It shows why the minimum payment is a trap — designed to keep you in debt as long as possible — and helps compare paying down a card against a balance transfer or consolidation loan. Financial counsellors use the same maths when building debt-repayment plans.