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Most mortgage calculators give you principal + interest and call it a day — which is why first-time buyers get blindsided by their actual monthly outlay $400-$800 higher than the "payment" they saw online. The real number is PITI: Principal, Interest, Taxes, and Insurance, plus PMI if you're under 20% down, plus HOA if applicable. A $400k home at 7% with 20% down isn't a $2,128 P&I payment — it's $2,128 + $400 property tax + $125 insurance = $2,653/mo all in. This calculator runs the full PITI breakdown so you know what's actually leaving your bank account on the 1st of every month, not the lender's marketing number.

Enter the home price and down payment.

How PITI works

Your monthly mortgage payment is four separate things bundled into one auto-debit:

  • Principal: the part that pays down your loan balance. Tiny in year 1, dominant by year 25.
  • Interest: the bank's cut on the unpaid balance. Massive in year 1, tiny by year 25.
  • Taxes: annual property tax divided by 12, escrowed into your payment, paid to the county on your behalf.
  • Insurance: homeowners insurance premium divided by 12, also escrowed.

P&I uses the amortization formula: M = P × i × (1+i)^n / ((1+i)^n – 1), where P is loan amount, i is monthly rate (annual ÷ 12), n is total months. The first month's payment is mostly interest; the last month's is almost all principal. This is why "paying extra principal early" is so powerful — every $1 of extra principal in year 1 saves you decades of compounding interest.

Worked example: $400k home, 20% down ($80k), 7% rate, 30-yr term, $4,800/yr tax, $1,500/yr insurance. Loan = $320,000. Monthly P&I = $2,128.97. Tax+ins = $525. PITI = $2,654/mo. Total paid over 30 years: $766,000 in P&I alone (interest = $446,000 — more than the original home price). That's why rate matters so much.

PMI and the 20% rule

If your down payment is less than 20% on a conventional loan, the lender requires PMI (private mortgage insurance) — typically 0.3% to 1.5% of the loan annually, billed monthly. It protects the lender, not you, against default. For a $320k loan at 0.5% PMI = $133/mo of pure cost.

PMI cancels automatically once your loan-to-value (LTV) hits 78% (per HPA federal law), or you can request cancellation at 80% LTV with a written request. Time to 78%: depending on your amortization, typically 8-11 years on a standard 30-yr at standard rates. You can speed it up with extra principal payments or by reappraising in a rising market.

FHA loans have MIP (Mortgage Insurance Premium) instead — and on most FHA loans originated after 2013, MIP does NOT cancel; it lasts the life of the loan unless you refinance into a conventional loan after hitting 20% equity. That's a big reason to refinance out of FHA when you can.

How to use this calculator

  1. Home price: purchase price.
  2. Down payment: cash to closing for the down. 20% avoids PMI on conventional; 3-5% is common minimum.
  3. Interest rate: current quoted rate from your lender (APR is slightly higher; this calc uses rate, not APR).
  4. Term: 30, 20, 15, or 10 years. 30 is most common; 15 saves massive interest.
  5. Annual property tax: look up the home's tax bill or estimate as 0.5-2.5% of home value depending on state.
  6. Annual home insurance: typically $1,200-3,000/yr depending on location and home value. Get a real quote.
  7. Monthly HOA: only if the property has an HOA (condos, planned communities). Can be $50-700+.
  8. PMI rate: 0.3-1.5%; lender quote will give exact rate. Auto-zero if down payment is 20%+.
  9. Output: total PITI(A), with P&I, T+I, PMI, HOA, and loan amount broken out.

Common scenarios

Sarah, first-time buyer in Dayton: $250k home, 5% down ($12.5k), 7.0%, 30-yr. Loan: $237.5k. P&I: $1,580. Property tax (1.5% Ohio): $313/mo. Insurance: $100/mo. PMI at 0.7%: $138/mo. Total PITI+PMI: $2,131/mo. Sarah's gross income needs to be ~$85k to qualify (28% front-end ratio).

Mike, move-up buyer in Texas: $450k home, 20% down ($90k), 6.75%, 30-yr. Loan: $360k. P&I: $2,335. Property tax (2.3% TX, no state income tax): $863/mo. Insurance: $200/mo (TX windstorm). Total PITI: $3,398/mo. Even at 20% down, the high TX property tax dominates — be aware of this when comparing across states.

Jen and Tom, 15-year refi: $300k balance, 6.0%, 15-yr. P&I: $2,532. That's $850 more per month than a 30-yr at the same rate ($1,683), but they'll pay only $156k total interest vs $440k on the 30-yr — saves $284k. If the higher payment fits, it's a no-brainer for paying off before retirement.

Empty-nester, $200k condo in Florida: 50% down ($100k), 7.0%, 15-yr, HOA $450/mo. Loan: $100k. P&I: $899. Property tax: $250/mo. Insurance: $250/mo (FL is expensive). HOA: $450. Total: $1,849/mo. The HOA is the second-biggest line item — common in Florida condos and a real expense to factor.

FAQ

What's PITI? +
Principal, Interest, Tax, Insurance — the four components of a real monthly mortgage payment. P&I goes to the lender; T&I goes into an escrow account and the lender pays your county and insurer when those bills come due. Add HOA and PMI for the full bottom line — that's what hits your bank account.
When does PMI go away? +
Automatically at 78% loan-to-value (LTV) per federal Homeowners Protection Act. You can request cancellation at 80% LTV with a written request to your servicer. Typical timing on a 30-year mortgage: 8-11 years. Extra principal payments and home appreciation can speed it up dramatically — if your $400k home appreciates to $500k, you may hit 78% LTV in 2-3 years and qualify for early removal after a $400-600 appraisal.
Should I do 15 or 30 years? +
15-year mortgages save massive interest — usually 50-65% of total interest vs the same loan at 30 years. The payment is roughly 50% higher though. Rule of thumb: if the 15-year payment fits comfortably (PITI under 25% of gross income), do the 15. If the 15 is tight, take the 30 and make voluntary extra principal payments — you get most of the savings with payment flexibility if cash flow tightens.
Interest rate vs APR — what's the difference? +
Interest rate is the cost of borrowing the principal. APR adds in origination fees, points, mortgage insurance, and closing costs amortized over the life of the loan — the full annualized cost. APR is always higher than rate. When comparing lender offers, compare APR; two lenders at the same rate can have very different APRs based on fees.
How much house can I afford? +
Lenders use 28/36 rules: front-end ratio (PITI / gross income) ≤ 28%, back-end ratio (PITI + all other debt / gross income) ≤ 36%. Aggressive lenders go to 43% back-end (qualified mortgage rule). Personal advice: keep PITI under 25% of gross. The bank will approve more than you should spend.
What are points and should I buy them? +
1 point = 1% of loan amount paid upfront to reduce the rate, typically by 0.25%. Break-even is usually 5-7 years. Worth it if you'll stay in the home 7+ years and have cash on hand. Not worth it if you'll move or refi within 5 years. Some lenders offer "negative points" (rebate at higher rate) — useful if you're cash-tight at closing.
Is mortgage interest still deductible? +
For loans up to $750k on primary residence and one second home (post-2017 tax law), interest is deductible — IF you itemize. With the 2024 standard deduction at $29,200 MFJ, most middle-class homeowners with smaller mortgages do NOT itemize. The "tax benefit" of buying is smaller than the conventional wisdom suggests. Run the numbers, don't assume.
Should I escrow taxes and insurance or pay them myself? +
If you have less than 20% down, the lender usually requires escrow. If you have 20%+ down, it's optional in most states. Pro escrow: smooths cash flow, no surprise bills. Pro DIY: hold the money in a savings account earning 4%+ and pay annually. For most people, escrow is the safer choice — forgotten property tax bills create real problems.
What about extra principal payments? +
Wildly effective on a long mortgage. One extra payment per year on a 30-yr cuts ~4 years off the loan and saves ~10% of total interest. Bi-weekly payments (26 half-payments = 13 full payments/year) achieve the same thing. Best leverage: extra payments in years 1-7 when balance is high. After year 15, extra payments save much less.
When does refinancing make sense? +
Rough rule: if you can drop the rate by 0.75-1.0% and you'll stay 3+ more years to recoup the closing costs (~2-3% of loan), refi makes sense. With rates volatile, watch for windows. Cash-out refis trade lower rate + extra cash for resetting the amortization clock — sometimes worth it, often not.