How it works
This calculator uses the standard fixed-rate amortization formula. Each payment is the same; early payments are mostly interest and later payments mostly principal.
Rates shown are your inputs, not quotes. Investment-property loans are often priced differently from owner-occupied loans — get a written quote and test a higher rate.
Formula
M = P × [r(1+r)^n] ÷ [(1+r)^n − 1]; r = annual rate ÷ 12, n = months; at 0% interest M = P ÷ n
Worked example
With the hypothetical defaults ($225,000 loan at 7% for 30 years):
| Monthly principal & interest | $1,497/mo |
|---|---|
| Total estimated housing payment | $2,247/mo |
| Loan amount | $225,000 |
| Total principal | $225,000 |
| Total interest over loan | $313,895 |
| Year 1 principal paid | $2,286 |
| Year 1 interest paid | $15,678 |
All figures in this example are hypothetical and chosen to illustrate the math. They are not current Houston market averages, quotes, or forecasts.
Frequently asked questions
Does this include PMI?
No. Add any mortgage insurance separately if it applies. Taxes, insurance, and HOA are optional inputs.
Where can I see current rate context?
FRED publishes the weekly Freddie Mac 30-year average. It's an owner-occupied benchmark; investor quotes typically differ.
See how every assumption interacts
The 713 Deal Generator combines financing, income, operating costs, and upfront cash into a printable report with stress tests and the 713 Metrics Score.
Run the Full 713 Deal Generator713 Metrics provides educational and informational tools based on user-provided assumptions. Results are estimates and do not constitute financial, investment, tax, legal, lending, appraisal, brokerage, insurance, or real-estate advice. Verify property-specific information independently and consult appropriate licensed professionals.