This is the calculator you use when someone asks "what will my payment be?" It returns the full PITI number: principal, interest, taxes, insurance, and PMI, plus HOA if you have one. If a calculator only shows you principal and interest it is hiding 25-35% of your real monthly cost — which is the number that decides whether you can actually afford the house.
Worked example:A $425,000 home with 20% down ($85,000) at 7.125% on a 30-year fixed gives you a $340,000 loan. Principal and interest is $2,290/month. Add 1.2% property tax ($425/mo), $1,400/year homeowners insurance ($117/mo), and no PMI at 80% LTV. Your real PITI is $2,832/month — $542 more than the P&I number most calculators show. That $542 is the part that surprises people.
The PITI formula in plain English
PITI has four parts plus two optional ones:
- Principal — the portion of your payment that reduces the loan balance. Tiny in year one, massive in year thirty.
- Interest — the bank's cut. Calculated monthly on the remaining balance, which is why paying extra principal early saves so much over the life of the loan.
- Taxes — property tax, billed annually by your county, usually collected monthly into an escrow account. U.S. average is 1.10% of home value, but ranges from 0.28% (Hawaii) to 2.47% (New Jersey).
- Insurance — hazard/homeowners insurance. Lenders require it. Typical range is $800 to $3,000/year depending on region, construction, and deductible.
- PMI (private mortgage insurance) — required when your loan-to-value is above 80% on a conventional loan. Typically 0.3%-1.5% of the loan balance per year. Drops off automatically at 78% LTV under federal law.
- HOA — homeowners association dues if your property has them. Condos and planned communities almost always do; single-family homes often do not.
The monthly P&I formula is P × (r/12) / (1 − (1 + r/12)^(−n)), where P is loan amount, r is annual rate as a decimal, and n is the number of months. Our calculator runs this exact formula — the same math a lender uses.
Three real scenarios at today's rates
Scenario 1 — First-time buyer, FHA-adjacent: $325,000 home, 5% down ($16,250), 7.25% rate, 30-year term. Loan is $308,750. P&I is $2,106. Tax at 1.1% is $298/mo. Insurance $105/mo. PMI at ~0.65% on a 95% LTV loan is $167/mo. Total PITI: $2,676/month.
Scenario 2 — Move-up buyer, 20% down: $550,000 home, 20% down ($110,000), 6.875% rate, 30-year. Loan $440,000. P&I $2,890. Tax at 1.3% is $596/mo. Insurance $175/mo. No PMI. Total PITI: $3,661/month.
Scenario 3 — High-end with HOA: $800,000 condo, 25% down ($200,000), 6.75% rate, 30-year. Loan $600,000. P&I $3,891. Tax at 1.0% is $667/mo. Insurance $95/mo (condo HO-6 is cheaper). HOA $450/mo. Total PITI+HOA: $5,103/month.
In every case, the non-P&I components add 27-31% on top of the base number. That is the real lesson of PITI.
How to stress-test your number
After you run a baseline, try these sensitivity checks:
- Rate +0.5%. If a quarter-point bump breaks your budget, you were not comfortably afford the home at the original rate.
- Tax rate +30%. Assessments get reassessed. New construction and gentrifying neighborhoods especially.
- Insurance +50%. If you are in a coastal, wildfire, or tornado zone, insurers have been repricing aggressively. Florida and California premiums have doubled in many ZIPs since 2022.
- PMI worst case. If you are putting less than 20% down, assume PMI is 0.85% of loan balance annually until you run the real quotes.
If the PITI stays below 28% of your gross monthly income under all four stress scenarios, the payment is safe. That is the "front-end ratio" lenders use, and it is also the ratio your future-self will thank you for respecting.
Where this calculator is approximate
The P&I math is exact. The tax, insurance, and PMI estimates are intelligent defaults based on national averages. To tighten the estimate:
- Property tax — look up the exact assessed rate on your county assessor's website.
- Homeowners insurance — get a real quote from your auto insurer or an independent agent.
- PMI — lenders price PMI by credit score (760+ saves you ~0.3% of loan balance annually vs. 680).
- HOA — the seller disclosure or condo docs have the exact number.
When you have those four inputs exact, the calculator result is within $10/month of what the lender will quote on the Closing Disclosure.