Credit Card Payoff Calculator
Use your own numbers after reviewing the formula and worked example.
Quick answer
Each month, interest is added to the balance and the remaining portion of the payment reduces principal.
Formula or method
Keep units, percentages and time periods consistent. The formula is useful as a transparent check on the calculator result and helps explain why changing one input changes the answer.
Step-by-step
- Convert APR to a monthly rate.
- Calculate interest on the current balance.
- Subtract the fixed payment.
- Repeat until the balance reaches zero.
Worked example
A payment only slightly above monthly interest reduces principal slowly; increasing the payment can shorten payoff time substantially.
How to interpret the result
The estimate assumes no new purchases and a steady rate and payment.
When the answer is used for a purchase, loan, payroll decision, construction order, school grade, health estimate or other real-world choice, verify the assumptions that matter in that context. Accurate arithmetic still depends on accurate inputs.
Common mistakes
- Continuing to add charges while using a no-new-charge estimate.
- Confusing a minimum payment with a fixed payment.
- Ignoring promotional or variable rates.
Frequently asked questions
Why can a small payment take so long?
Interest consumes part of every payment.
What if payment is below monthly interest?
The balance can grow.
Does this include new purchases?
No, unless the calculator specifically models them.