💳 Credit Card Payoff Calculator

Enter your credit card balance, APR, and planned fixed monthly payment to calculate how many months it will take to pay off and the total interest you'll pay.

The formula behind the months

With B the balance, P the monthly payment and r the monthly rate (APR / 12, as a decimal), the payoff has a closed form - nothing is simulated:

n = -ln(1 - r x B / P) / ln(1 + r)

total paid = n x P
interest   = total paid - B

The defaults - $5,000 at 18% APR, $150 a month - give r = 0.015 and n = -ln(0.5) / ln(1.015) = 46.6 months, or 3 years 11 months. You hand over $6,983 to clear $5,000, so $1,983 of it is interest.

Why the payment has to beat the interest

That $5,000 balance accrues $75 in its first month at 18%. Pay $75 or less and the balance never moves, so the tool refuses the input rather than printing an infinite payoff date. Going the other way is dramatic: lift the payment from $150 to $200 and payoff drops to 31.6 months with $1,314 of interest, so $50 a month buys back 15 months and $669.

This assumes a fixed payment and no new spending. A card's own minimum is usually a percentage of the balance, so it shrinks as you pay and stretches payoff far beyond a flat payment of the same starting size.

Frequently asked questions

How long does it take to pay off $5,000 at 18%?

At $150 a month, 46.6 months - just under four years - and $1,983 of interest. At $200 a month it is 31.6 months and $1,314.

What is the smallest payment that actually reduces my balance?

Anything above balance x APR / 12. On $5,000 at 18% that is $75 a month, and paying $80 would take more than 15 years. Aim well clear of that line.

Does the result assume I stop using the card?

Yes. The balance only ever falls in this model, so new spending at the same APR pushes the date out.