Credit Card Calculator
See how long a credit card balance takes to clear and what the interest really costs.
Inputs
Minimum payment mode shows the worst-case scenario many cardholders face.
Months to Pay Off
54
Total Interest Paid
$3,044.95
Total Amount Paid
$8,044.95
First Month's Interest
$95.79
Step by step
Monthly interest rate
22.99% ÷ 12
= 1.9158%
First month's interest
$5,000.00 × 1.9158%
= $95.79
Number of payments (nper)
−ln(1 − $5,000.00 × 1.9158% ÷ $150.00) ÷ ln(1 + 1.9158%)
= 53.63 months
Total interest paid
$150.00 × 53.63 − $5,000.00
= $3,044.95
How it works
Credit cards compound interest monthly on the outstanding balance. A fixed monthly payment lets you forecast an exact payoff date using the NPER formula. Minimum payments are more insidious: because they're calculated as a percentage of the shrinking balance, each payment is smaller than the last — a $5,000 balance at 23% APR with a 2% minimum takes over 30 years to clear and costs more in interest than the original balance.
Formulas
Monthly interest accrued
Monthly interest = Balance × (APR / 12)
- B
- Current balance
- APR
- Annual percentage rate as decimal
Fixed payment payoff periods
n = −ln(1 − Balance × r / Payment) / ln(1 + r)
- n
- Number of months
- r
- Monthly rate
- P
- Fixed monthly payment
Frequently Asked Questions
Why do minimum payments barely make a dent?
Minimum payments are typically 1–3% of the balance. At a 22% APR, roughly 22%/12 ≈ 1.83% of the balance accrues as interest each month. A 2% minimum payment leaves only 0.17% going to principal — the debt shrinks at a crawl while interest compounds.
What's a realistic minimum payment percentage?
Most US issuers use 1–2% of the balance plus any fees and interest, or a fixed floor (often $25–35), whichever is greater. Some cards use a flat 1% of balance plus the month's interest, which is equivalent to paying interest-only plus a tiny sliver of principal.
Does this account for new charges on the card?
No — this calculator assumes no new purchases are added to the balance. In practice, continuing to use the card while paying it down is like filling a bucket while it drains.