Credit Card Payoff Calculator
Estimate payoff time and interest from a fixed monthly payment; actual card terms can differ.
Formula and sources updated · Data sources · 1View algorithm, constants and default inputs (JSON)
Breakdown
About this calculator
Estimate payoff time with a fixed monthly payment using a simplified monthly-interest model (APR ÷ 12). Issuer methods can accrue interest daily and include fees or multiple APRs, so this is not a statement-level forecast.
Worked example
calculated with the default values below
Card balance 5,000 $ · Annual interest rate (APR) 22 % · Monthly payment 200 $ Months to pay off 34 · Total interest paid 1,749.88 $ · Total paid 6,749.88 $ · Current monthly interest (not a minimum payment) 91.67 $
Data sources
Disclaimer
These calculators give estimates for general information only. They are not financial, tax or investment advice and do not take your personal circumstances into account. Before borrowing, investing or filing, confirm the numbers with a qualified adviser in your jurisdiction.
Implementation source
This record describes the implementation used by this page. It is not independent validation. External references, when available, support only the stated formula or definition; estimates and custom rules retain their own assumptions.
Formula and variables
B_0 = B; B_{n+1} = B_n × (1 + i) − min(P, B_n × (1 + i)); N = min{n : B_n ≤ 0.01}
- B
- Current balance
- APR
- Annual percentage rate
- P
- Monthly payment
- i
- Monthly rate = APR ÷ 1200
- n
- Month index, n = 0, 1, 2, …
- N
- Months to pay off
This simplified fixed-payment model applies APR ÷ 12 to the balance once per month, then applies the payment. It omits daily periodic rates, average daily balances, new purchases, multiple APR buckets, fees and issuer minimum-payment rules. Iteration is capped at 1,200 months; longer payoffs are reported beyond the horizon.
Frequently asked questions
How does the payoff estimate calculate interest?
It applies APR ÷ 12 to the remaining balance once per month, then applies the fixed payment. Real issuers may accrue interest daily, use average daily balances, apply different APRs or fees, and require a minimum payment, so use this as an estimate rather than a statement forecast. A result over 1,200 months is shown as beyond the model horizon.