How a credit card payoff is calculated

One card in one paragraph

A credit card payoff is the time and interest it takes to drive one balance to zero. The credit card payoff calculator keeps a single balance, an annual percentage rate, a fixed minimum, and the fixed amount you will actually send. Each month it adds interest, then subtracts the payment. It compares those two payments on the same card. It does not rank several debts.

When to use

Use it when one card is the question: what does the minimum cost, and what does a higher payment save. Use the debt snowball guide when you have more than one balance and you want the smallest balance or the highest rate to get the extra money. This page does not roll a finished minimum into the next debt. That rollover is the snowball and avalanche model.

The formula in plain English

Monthly rate = APR / 12
Interest this month = balance × monthly rate
New balance = balance + interest − payment

The payment is the fixed minimum or the fixed amount you type. The last payment is smaller if the remaining balance is less than that amount. If the payment is not larger than the interest, the balance does not fall. The run stops at 50 years and reports that the card was not paid off. The chart draws at most 30 years.

The month count is the number of those steps until the balance is zero. Total interest is the sum of the monthly interest charges. Interest saved is the minimum path’s interest minus the higher payment’s interest, and only when both paths finish.

A worked example

A balance of 5,000 at 19.9% APR. A fixed minimum of 150 pays the card in 49 months and about 2,339 of interest. A fixed payment of 300 pays it in 20 months and about 901 of interest. The higher payment saves about 1,438 of interest and 29 months. At a zero rate the same comparison is only about time, because no interest accrues. A payment that does not cover the first month’s interest never reaches zero inside the cap.

How to read the result

The four timing cards are the minimum path and your payment, each with months and interest. Interest saved and months saved are the gap between them. A negative gap means the payment you typed is smaller than the minimum, so it costs more or takes longer. Scenario B is a second card with its own balance and rate. The two cards are not combined, and paying one does not reduce the other.

The APR slider goes high enough for revolving rates that are quoted as a steep annual figure. Portuguese and Spanish pages start from local currency defaults. The formula is the same.

Common mistakes

Treating a percentage-of-balance minimum as a fixed dollar amount. Many issuers reduce the minimum as the balance falls. This page holds the payment still, which is the conservative comparison against a fixed plan you choose.

Using the snowball tool for a single card and expecting a different interest total. With one debt, snowball and avalanche are the same path.

Ignoring a minimum that does not cover interest. The warning on the page is that case.

FAQ

Is this one card or a whole debt list?

One card. Several debts, with extra money aimed at the smallest balance or the highest rate, belong on the debt snowball calculator.

Why is the minimum a fixed amount?

So you can compare it with another fixed amount. A minimum that shrinks with the balance is a different contract. You can still type today’s minimum and see the cost of staying there.

What if my payment is below the interest?

The balance grows or stalls. The page stops at 50 years and does not pretend the card is paid off.

Does the rate include fees?

No. Type the annual rate you want to test. Fees, promotional periods, and a rate that changes after a few months are outside the model.

Is this financial advice?

No. It is a payoff illustration that runs in your browser.

Related guides

• Debt snowball versus avalanche — several balances, and where the extra payment goes.
• How big an emergency fund should be — cash set aside before a higher card payment is a different job.

Try it with your figures

Open the credit card payoff calculator, set the balance, the APR, the minimum, and the payment you can send. The link keeps the inputs. Add Scenario B only when you want a second card beside the first.