PITI Calculator

Background.

A PITI calculator combines the four components of a US mortgage payment that never actually arrive separately: Principal, Interest, Taxes, and Insurance. Quanta already has dedicated calculators for each individual piece — a mortgage calculator for principal and interest, a property tax calculator, a homeowners insurance calculator, and a PMI calculator for private mortgage insurance — and each of those tools is the right place to work out its specific number in detail. This calculator's entire reason for existing is different: it is the one place that adds all four (plus optional PMI and HOA dues) into the single dollar figure that will actually leave your bank account every month, because that combined number, not any one of its four ingredients in isolation, is what a lender uses to qualify you for a loan and what your household budget actually has to absorb.

The gap between the 'mortgage payment' most people picture and the real monthly housing cost is large and systematic. A borrower who runs a standalone mortgage calculator on a $350,000 loan at 6.5% over 30 years gets a principal-and-interest figure of $2,212.24 and, if they stop there, will be caught off guard when the actual bank draft is meaningfully higher. Add a typical property tax bill of $4,200 per year ($350/month), a homeowners insurance premium of $1,440 per year ($120/month), and — if the down payment was under 20% — a PMI premium of $150/month, and the true monthly payment climbs to $2,832.24, roughly 28% above the bare principal-and-interest figure. That gap is not a rounding error or a lender markup; it is simply the rest of the cost of owning a home that a principal-and-interest-only calculator was never designed to show.

Each of the four required PITI components has a different character. Principal and interest are fixed by the loan contract for the life of a standard fixed-rate mortgage and never change unless you refinance. Property tax is set annually by your county or municipal assessor against your home's assessed value and typically rises over time as the home appreciates or the local tax rate changes. Homeowners insurance is a market-priced annual premium that can rise significantly after a claim, a rate filing, or increased regional catastrophe risk (coastal wind, wildfire, and hail exposure have all driven meaningful premium increases in recent years). Because property tax and insurance both change independently of your mortgage rate, and neither is fixed for 30 years the way principal and interest are, a lender-escrowed PITI payment is reviewed and adjusted annually even on an otherwise-unchanged fixed-rate loan — a detail that surprises many first-time buyers who assumed their 'mortgage payment' would never move.

PMI and HOA dues sit slightly outside the strict four-letter PITI acronym but matter just as much to a real household budget, which is why this calculator reports both a strict PITI figure (the literal four components) and a separate 'total monthly payment' figure that folds PMI and HOA in on top. Private mortgage insurance is required by most conventional lenders whenever the down payment is under 20% (a loan-to-value ratio above 80%), and under the federal Homeowners Protection Act of 1998 it is automatically cancelled once the loan balance is scheduled to reach 78% of the original property value — meaning the 'total' figure this calculator reports is not permanent for most buyers, even though it feels permanent on day one. HOA or condo association dues, by contrast, generally do not expire and are a recurring fact of ownership for any property inside a homeowners association or condo building, covering shared amenities, building insurance, and common-area maintenance.

The practical use case for a combined PITI figure is underwriting math. Mortgage lenders apply a 'front-end' debt-to-income ratio — commonly a maximum of 28% of gross monthly income — specifically against the PITI figure (sometimes including PMI and HOA in the calculation, depending on the loan program), not against principal and interest alone. A household comparing two homes with identical loan amounts but very different property tax rates or HOA structures can look dramatically different once the full PITI (or PITI+PMI+HOA) figure is computed, even though the 'mortgage payment' quoted by a real estate agent might look identical for both. This calculator exists specifically to surface that full picture in one place, sourcing each of its four core inputs from the dedicated calculators already built for exactly that purpose: run the mortgage calculator, property tax calculator, homeowners insurance calculator, and PMI calculator individually if you need to derive any one of these dollar figures from scratch, then bring the results here to see the true combined monthly cost.

What is piti calculator?

PITI is a US mortgage industry acronym standing for Principal, Interest, Taxes, and Insurance — the four components that together make up the standard monthly payment on an escrowed mortgage. Principal is the portion of the payment that reduces the loan balance. Interest is the lender's charge for the outstanding balance, calculated each month against the remaining principal under a standard amortization schedule. Taxes refers to one-twelfth of the annual property tax bill assessed by the local county or municipal government against the home. Insurance refers to one-twelfth of the annual homeowners (hazard) insurance premium required by virtually every mortgage lender to protect the collateral against fire, wind, and other covered perils. Lenders collect all four components together in a single monthly payment and hold the tax and insurance portions in an escrow (impound) account, from which they pay the actual annual tax and insurance bills on the borrower's behalf when due — a structure required under the federal Real Estate Settlement Procedures Act (RESPA) whenever an escrow account is established. Two additional costs commonly ride alongside PITI without being part of the acronym itself: private mortgage insurance (PMI), required on most conventional loans with less than 20% down and protecting the lender (not the borrower) against default losses, and homeowners association (HOA) or condo association dues, which fund shared building or community expenses. Lenders computing a borrower's 'front-end' debt-to-income ratio for mortgage qualification purposes typically use the PITI figure (and, on some loan programs, PITI plus PMI and HOA) as the numerator, which is why understanding the full combined figure — not just the bare principal-and-interest payment — matters for both budgeting and loan qualification.

How to use this calculator.

1. 01Enter the loan amount, interest rate, and loan term — the same three inputs the standalone mortgage calculator uses. If you need to derive the loan amount from a home price and down payment percentage, use that calculator first.
2. 02Enter your annual property tax bill in dollars. If you only know your home's assessed value and local tax rate, use the property tax calculator to work out the dollar figure first.
3. 03Enter your annual homeowners insurance premium in dollars. If you only have a quoted rate per $1,000 of coverage, use the homeowners insurance calculator to work out the dollar figure first.
4. 04If your down payment was under 20%, enter your monthly PMI premium — use the PMI calculator if you only know your down payment percentage and PMI rate. Leave at $0 if you put 20%+ down or your PMI has already cancelled.
5. 05If the property carries HOA or condo association dues, enter the monthly amount. Leave at $0 if none apply.
6. 06Read 'Monthly PITI (strict)' for the literal principal + interest + tax + insurance figure most lenders quote as your PITI payment.
7. 07Read 'Total monthly payment' for the complete, true monthly cost including PMI and HOA — the number that should actually appear in your household budget.

The formula.

The calculation runs in three stages. Stage one computes the principal-and-interest payment using the standard fully-amortizing loan formula: monthlyPI = loanAmount × [r(1+r)ⁿ] / [(1+r)ⁿ − 1], where r is the monthly interest rate (annual rate ÷ 100 ÷ 12) and n is the total number of monthly payments (loan term in years × 12). For the special case of a 0% interest rate, the formula is guarded and reduces to simple linear amortization: monthlyPI = loanAmount / n, avoiding a division-by-zero in the standard formula's denominator. Stage two converts the two annual dollar inputs — property tax and homeowners insurance — into monthly figures by dividing each by 12, mirroring exactly how a lender's escrow account prorates an annual bill into twelve equal monthly collections. Adding these two monthly figures to the principal-and-interest payment from stage one produces monthlyPITI, the strict four-letter PITI figure. Stage three adds the two components that ride alongside PITI without being part of the acronym: the entered monthly PMI premium and monthly HOA dues, both defaulting to $0 if not applicable. Adding both to monthlyPITI produces totalMonthlyPayment, the complete real-world monthly housing cost. A separate annualPITI figure — monthlyPITI × 12 — is reported for convenience when comparing against annual income under a lender's front-end debt-to-income guideline (commonly a maximum of 28% of gross annual income for PITI, though specific thresholds and whether PMI/HOA are included vary by loan program and lender). All arithmetic runs in arbitrary-precision decimal math via decimal.js, so no floating-point rounding error accumulates across the multiple monthly-to-annual and annual-to-monthly conversions this calculator performs.

A worked example.

Frequently asked questions.

References& sources.

1. [1]Consumer Financial Protection Bureau — Owning a Home (escrow accounts, loan estimates, and total monthly payment guidance)
2. [2]Consumer Financial Protection Bureau — What is private mortgage insurance?
3. [3]Internal Revenue Service — Publication 530: Tax Information for Homeowners
4. [4]U.S. Department of Housing and Urban Development — Real Estate Settlement Procedures Act (RESPA), escrow account rules
5. [5]Consumer Financial Protection Bureau — Loan Estimate and APR disclosure rules under TILA-RESPA
6. [6]Federal Reserve Board — Homeowners Protection Act of 1998 (automatic PMI cancellation at 78% loan-to-value)