Pick a fixed payment or a minimum payment rule. Add extra per month and any fees. We’ll estimate months to payoff, total interest, and show your schedule.
Balance & APR
Payment method
If your payment is less than monthly interest + fees, the balance grows (negative amortization). We’ll flag it.
All calculations run in your browser.
Months to payoff
0
Total interest
$0
Estimated payoff date
—
First 12 months
Month
Payment
Interest
Fees
Principal
Balance
CSV export includes the full schedule.
How to use
Enter your balance and APR.
Pick Fixed or Minimum payment and fill the fields.
Add an extra monthly amount and any fees (optional).
Hit Calculate. Check the metrics and the first-year schedule. Export CSV if you want the full table.
Assumptions & rules
Interest compounds monthly at APR/12. Interest applies to the starting balance of each month.
Minimum payment = max(% of balance, floor) + extra. If this is less than (interest + fees), we warn and stop stats.
Final month payment is trimmed so you don’t “overpay.”
Fees are added monthly before payment is applied.
All numbers are estimates; statements and card agreements govern.
Results explained
Months to payoff: Number of months until balance reaches zero (with current inputs).
Total interest: Sum of all interest charges across the schedule.
Estimated payoff date: Today plus the months to payoff.
Schedule: Payment breakdown each month into interest, fees, principal, and new balance.
FAQ
Why did my balance increase after a payment?
Your payment was less than interest + fees for that month. That’s negative amortization. Increase the fixed payment or the min payment settings.
Where do the minimum payment defaults (2% / $25) come from?
They’re common industry values, but your issuer may use different terms. Check your statement.
Does this include daily compounding?
No. We model monthly compounding using APR/12. That keeps the tool simple and transparent.
Can I model a promotional 0% APR?
Yes—set APR to 0. You’ll still see fees applied if you entered any.