Formula & method
New balance = old balance × (1+r) − scheduled payment − extra payment
The calculator simulates every payment period, so irregular payoff timing and interest savings remain visible.
Assumptions
- Inputs remain in your browser and are not saved.
- Rates are converted to the payment frequency shown.
- Results are rounded for display; internal calculations retain precision.
Example calculation
Example
Adding $250 a month to a $300,000 mortgage can remove years from the term.
Important
Educational estimates only — not financial, tax or legal advice.