What PITI Actually Means
Most online mortgage calculators show you only principal and interest — the loan payment. But that's not what you actually pay each month. Your real housing cost is PITI: Principal, Interest, Taxes, and Insurance, plus PMI if you put less than 20% down, plus any HOA dues. On a typical loan, taxes and insurance can add 20–30% on top of the loan payment, which is why a house that "pencils out" on a P&I-only calculator can blow your budget in real life.
The 20% Down / PMI Tradeoff
Private mortgage insurance protects the lender, not you, and it's required whenever your loan-to-value ratio is above 80% (less than 20% down). It typically runs 0.3–1.5% of the loan per year. The good news is it isn't permanent — once your balance falls to 80% of the home's original value, you can request cancellation, and it drops automatically at 78%. The down-payment table above shows exactly what PMI costs you at each level so you can decide whether stretching to 20% is worth it.
Why the Rate Matters More Than the Payment
A mortgage runs for decades, so small rate differences compound into enormous numbers. The rate comparison above shows the total-interest swing from a half-point move in either direction — often tens of thousands of dollars on a 30-year loan. Shop at least three lenders, and remember that paying points up front can make sense if you'll hold the loan long enough to recoup the cost.
This calculator is for planning and education only and does not constitute a loan offer or financial advice. Property tax, insurance, and PMI vary by location and lender — confirm exact figures with your lender's Loan Estimate.