What will my mortgage payment be?

The loan is the price minus the down payment. Principal and interest on it come from the standard amortization formula: a fixed payment, at your annual rate divided by twelve, that retires the balance exactly at the end of the term. Early payments are mostly interest because the balance is large; later ones are mostly principal because it is small. The schedule under the number shows that shift one year at a time.

The rest of the payment is the carrying cost of owning the home, which lenders usually collect with the payment into escrow. Property tax is a percent of the home's value spread over twelve months. Homeowners insurance is an annual premium divided by twelve. Private mortgage insurance is a percent of the loan, charged only when the down payment is under 20% of the price. HOA dues are whatever you enter. The hero figure is the first month's total, with all of those in it.

Mortgage insurance does not last the life of the loan. The calculator follows the Homeowners Protection Act as CFPB describes it: the charge ends in the month the scheduled balance reaches 78% of the original price. The result reports that month and the lower payment after it, and the cost-of-the-loan figure counts only the months it applies.

Extra principal, if you enter it, is paid on top of the regular payment every month. It does not lower the payment; it shortens the loan and cuts the interest, because every later month charges interest on a smaller balance. The result reports the months and the dollars saved against the same loan with no extra payment.

The defaults are published statistics, not guesses: the weekly Freddie Mac survey rate, the effective property tax rate from Census data, the countrywide average homeowners premium from state regulators, and the middle of Freddie Mac's published range for mortgage insurance. The price and down payment are examples to be replaced. Every figure on this page and in the JSON twin comes from one function, so the two never drift.

At the published defaults, a $400,000 home with $80,000 down means a $320,000 loan at 6.65% over 30 years. The full monthly payment is $2,484: $2,054 of principal and interest, $296 of property tax, and $133 of insurance. No mortgage insurance, because the down payment is 20% of the price. Over the life of the loan you repay the $320,000 and pay $419,544 of interest on top of it.

The same home with $40,000 down costs $2,920 a month: a bigger loan, plus $180 of mortgage insurance until month 111, when the payment falls to $2,740. Mortgage insurance adds $19,980 over those months, and the interest over the loan rises to $471,986.

Here is the full payment across common prices at the default rate, with 20% down and with 10% down. The 10% column carries mortgage insurance in its first years. Change any input above and the page recomputes as you type.

The payment is close to linear in price because every part of it scales with the price or the loan. The interest figure is the one most people have never seen: at today's rates a 30-year loan pays back well over its own principal in interest, which is the arithmetic behind both the case for a larger down payment and the case for a shorter term.

The calculator ranks its own drivers above, in dollars of monthly payment per step, for the inputs you entered. The steps are the sizes people actually negotiate in: a quarter point of rate, ten thousand dollars of price or down payment, a quarter point of property tax, a hundred dollars of extra principal. Read the list as what one move buys, not as a league table.

The rate is the lever with the longest reach. A quarter point at the defaults adds $53 a month and $19,163 of interest over the loan, because it is charged on every dollar of the balance for every month it is outstanding. Rate buy-downs, a better credit score, and timing all work through this one number.

The term trades the payment against the total. The 15-year loan costs more each month and far less over its life; the 30-year is the reverse. Pick a term under the number to see both sides for your inputs. Extra principal is the way to get a 15-year result on a 30-year loan without giving up the lower required payment.

The down payment lowers the loan one-for-one and, at the 20% line, removes mortgage insurance from the payment. Crossing that line is worth more than the same dollars anywhere else in the down payment.

Property tax and insurance never amortize away. A point of property tax on a $400,000 home is $333 a month forever, and both grow with reassessments and renewals. They are also the two defaults most likely to be wrong for a specific home, so replace them with the county rate and a real quote when you have them.

The rate is a national survey average for a borrower with strong credit; the rate you are offered depends on your score, the loan type, points paid, and the lender. An adjustable-rate loan is not modeled at all: the payment here is fixed for the term.

Property tax and insurance are national averages. Tax varies by an order of magnitude between states and insurance has been rising fastest where weather risk is highest. Both are estimates at the start and rise over time, and neither is in the lender's control. The principal and interest figure is the only part of the payment that is fixed for the life of the loan.

Closing costs, points, and prepaid escrow are not in this calculator. They are the cash you bring to the table on top of the down payment, and the house affordability calculator reports them. Tax deductibility of mortgage interest, which depends on whether you itemize, is not modeled either.

This calculator is built to be used without a browser. Every input is a query parameter on this page, and the same parameters on the JSON twin return the complete answer as a document.

GET /tools/mortgage-payment.json?price=450000&down=45000

The response carries inputs after parsing and clamping, result with the loan, the monthly breakdown, the payment after mortgage insurance ends, the interest and total cost over the loan, the yearly schedule, plus sensitivity tables by rate, term, and extra principal, drivers ranked by effect with a plain sentence each, assumptions that say for every field whether you supplied it and which source the default came from, sources with URLs and as-of dates, warnings, a disclaimer, and in tool the canonicalUrl and jsonUrl that carry only your non-default parameters. The canonical URL is the answer's permanent address; use it when you cite the number.

Parameters, all optional, in any order:

• price ($), default $400,000.
• down ($), default $80,000.
• rate (%), default 6.65%, from Freddie Mac Primary Mortgage Market Survey.
• term (years), default 30 years.
• taxRate (%), default 0.888%, from NAHB Eye On Housing, Property Taxes by State, 2024 (American Community Survey).
• insurance ($), default $1,600, from NAIC, Examining Homeowner Property Insurance Market Dynamics, 2018 to 2024.
• hoa ($ per month), default $0 per month.
• pmiRate (%), default 0.6%, from Freddie Mac, Breaking down PMI.
• extra ($ per month), default $0 per month.

Values accept plain numbers and loose human formats such as 100k, $100,000, or 6.5%. Unknown parameters are ignored, values outside a field's range are clamped and reported in warnings, and the endpoint never fails on bad input. Responses are cacheable for a day; the defaults change when their sources publish, and tool.version changes when the method does.

• Freddie Mac Primary Mortgage Market Survey, as of 2026-08-20. 30-year fixed-rate mortgage average 6.65%; 15-year 5.95%.
• NAHB Eye On Housing, Property Taxes by State, 2024 (American Community Survey), as of 2025-11-26. National effective property tax rate $8.88 per $1,000 of home value (0.888%).
• NAIC, Examining Homeowner Property Insurance Market Dynamics, 2018 to 2024, as of 2026-07-31. 2024 average homeowners premium per policy: $1,600 countrywide.
• Freddie Mac, Breaking down PMI, as of 2026-08-21. Private mortgage insurance typically costs $30 to $70 per month for every $100,000 borrowed (0.36% to 0.84% of the loan per year). Required on conventional loans with less than 20% down.
• CFPB, When can I remove private mortgage insurance (PMI) from my loan?, as of 2023-08-28. Under the Homeowners Protection Act a servicer must automatically terminate PMI on the date the principal balance is scheduled to reach 78% of the home's original value; the borrower may request cancellation at 80%.

Default values on this page: rate 6.65% (Freddie Mac Primary Mortgage Market Survey), property tax 0.888% of value (NAHB Eye On Housing, Property Taxes by State, 2024 (American Community Survey)), insurance $1,600 a year (NAIC, Examining Homeowner Property Insurance Market Dynamics, 2018 to 2024), mortgage insurance 0.6% of the loan (Freddie Mac, Breaking down PMI), ending at 78% of the original price (CFPB, When can I remove private mortgage insurance (PMI) from my loan?). The price and down payment defaults are examples.

Carlo is a personal finance agent. It knows your accounts, debts, and goals, so instead of a payment on an example home it can tell you what a specific home does to your savings rate, your taxes, and the other things you are working toward. Text it the question.

ask carlo anything(415) 376-5678