Mortgage Calculator
Calculate your P&I payment, full PITI with taxes and insurance, total interest over the loan life, and view the complete amortization schedule.
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Enter home price and interest rate to calculate.
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How this works
The standard amortization formula is: M = P × [r(1+r)^n] / [(1+r)^n − 1], where P is the loan principal, r is the monthly interest rate (annual rate ÷ 12 ÷ 100), and n is the total number of payments. This gives you the fixed monthly payment where each installment covers that month's interest and retires a bit of principal.
PITIadds property taxes, homeowner's insurance, HOA dues, and PMI (when applicable) on top of the P&I payment. Lenders use PITI to calculate your debt-to-income ratio. For investors, PITI is also the expense line in your cash flow model — it's what leaves your account every month.
The amortization tableshows you exactly how much of each payment goes to principal vs. interest. In the early years of a 30-year mortgage at 7%, roughly 80% of your payment is interest. After 10 years, the balance barely moves compared to what you've paid — which is why refinancing or selling early can feel frustrating.
For investors evaluating a rental property, plug this calculator's monthly P&I output into the Cash Flow Calculator to see how financing affects your monthly return. The difference between a 6% and 7.5% rate on a $250K loan is about $220/month — significant when you're underwriting a $200/month cash flow target.
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Frequently Asked Questions
What does PITI mean?
PITI stands for Principal, Interest, Taxes, and Insurance — the four components of a total monthly mortgage payment. Lenders qualify borrowers based on PITI, not just P&I.
When does PMI apply?
Private Mortgage Insurance (PMI) is required when your down payment is less than 20% of the purchase price. This calculator automatically shows the PMI field when your down payment falls below that threshold. PMI typically costs 0.5–1.5% of the loan amount annually.
What is the difference between a 15-year and 30-year mortgage for investors?
A 15-year mortgage has a higher monthly payment but far less total interest. For buy-and-hold investors, a 30-year loan preserves cash flow (the investor's primary metric). For primary residences or properties you plan to pay off, a 15-year loan can save tens of thousands in interest.
How does the amortization schedule work?
Early payments are mostly interest; later payments shift toward principal. This is called front-loaded amortization. It is why selling after 5 years on a 30-year loan means you've paid surprisingly little principal — the early payments went almost entirely to the lender.