What this calculator helps you do
Estimate payoff time and interest when a fixed monthly payment is applied to a revolving balance. The calculation runs entirely in your browser; SENNA Finance does not receive the values entered into this tool.
Worked example
Using the default example—card balance of $7,500, annual percentage rate of 22.9%, monthly payment of $300—the calculator returns estimated payoff time of 2 years 11 months; total interest: $2,789.67; total paid: $10,289.67. Change the assumptions to match your own case rather than relying on the example.
Formula and calculation basis
Inputs are converted to the periodic units required by the formula. Results are calculated with full JavaScript numeric precision and rounded only for display.
How to interpret the result
A payment only slightly above monthly interest can produce a very long payoff. Increasing the fixed payment usually has a strong effect on time and interest.
Common mistakes to avoid
- Continuing new purchases while using a payoff projection.
- Ignoring promotional-rate expiry or variable-rate changes.
- Using a payment that does not cover monthly interest.
Limits and assumptions
The model assumes no new transactions, a constant rate, and one payment per month.
Outputs are estimates, not contractual quotations, regulated disclosures, tax advice, investment advice, or a substitute for professional review.
Frequently asked questions
Why does payoff take so long at a small payment?
Interest consumes a large share of a small payment, leaving little principal reduction.
What if the payment is below interest?
The balance will not amortize; the tool shows a warning.
Are late fees included?
No. Add them to the balance or use issuer statements for an exact plan.
Sources and reference context
External references provide educational context and do not imply endorsement of SENNA Finance.