Mortgage Payoff Calculator
Mortgage & Extra Payments
Savings Summary
| Normal Monthly Payment | — |
|---|---|
| Accelerated Payoff Term | — |
| Time Saved | — |
| Total Interest Saved | — |
| Total Interest (Original) | — |
| Total Interest (New) | — |
Visual Breakdown
Enter values and press Calculate to see the loan breakdown pie chart and balance path line chart.
How Extra Payments Accelerate Mortgage Payoff
Making additional payments on your mortgage reduces the outstanding principal balance directly. Because interest is computed monthly based on the remaining balance, a smaller principal balance results in lower interest charges. Every dollar of interest saved accelerates your payoff timeline.
Payoff Acceleration Math
For each month ***t***:
- **Interest Portion:** ***I_t = Balance_{t-1} × i***
- **Base Principal Portion:** ***P_t = M - I_t***
- **Extra Applied:** ***Extra_t = Extra_{monthly} + (Extra_{annual} \text{ if month matches}) + (Extra_{onetime} \text{ if month matches})***
- **Total Principal Paid:** ***P_{total} = \min(P_t + Extra_t, Balance_{t-1})***
- **New Balance:** ***Balance_t = Balance_{t-1} - P_{total}***
Disclaimer. This calculator is for informational purposes only. Some lenders apply prepayment penalties or require special instructions to apply additional funds to principal rather than prepaying future scheduled payments. Check with your servicer.