Mortgage Calculator

A mortgage payment is more than principal and interest. This calculator adds estimated property taxes, homeowners insurance, and PMI so you see the full monthly obligation. For most buyers the extras add 20–35% on top of principal and interest — budgeting on P&I alone is how buyers get surprised.

What is a mortgage payment?

A mortgage is a loan secured by the home you buy: the house itself is the collateral, which is why mortgage rates are lower than almost any other consumer borrowing rate. In the United States, the standard product is a 30-year fixed-rate mortgage — equal monthly payments, a rate that never changes, and a balance that reaches zero exactly at the final payment. Fifteen-year fixed loans and adjustable-rate mortgages (ARMs) are the main alternatives, trading higher payments for far less interest, or a lower initial rate for future uncertainty.

The quoted 'mortgage payment' most people picture is only principal and interest. The actual monthly obligation — what leaves your bank account — usually also includes property taxes and homeowners insurance, collected by the lender into an escrow account and paid on your behalf when bills come due. If your down payment is under 20%, add private mortgage insurance (PMI), a policy that protects the lender, not you, and that you pay for. Lenders summarize the four parts as PITI: principal, interest, taxes, insurance.

Because a mortgage is likely the largest loan of your life, small differences compound enormously. A quarter-point of rate on a $382,500 loan is worth roughly $23,000 of interest over 30 years, and five years of term difference changes total interest by six figures. This is why the smartest shopping happens before the purchase: rate, term, down payment, and the tax and insurance load of the specific property all belong in the same calculation — which is exactly what this page puts together.

How a mortgage payment is calculated

The calculator first subtracts your down payment from the price to get the loan amount, then applies the amortization formula to find the monthly principal and interest. It then walks the loan month by month, tracking the balance. Property tax and insurance are entered as annual amounts and divided by 12, because that is how escrow collects them. PMI is entered as an annual percentage of the loan amount, also divided by 12, and is charged only while the balance stays above 80% of the home's price — the standard cancellation threshold — so the calculator reports both the payment while PMI applies and the lower payment afterward, plus roughly how many months PMI lasts.

All three extras are labelled estimates for good reasons. Property taxes are set by your county or municipality and change as assessments and rates change; a common planning figure is 1.0–1.25% of the home's value per year, but real rates vary widely by state and locality. Insurance depends on the home, its location, and coverage choices. PMI pricing depends on your credit score and down payment; 0.55% per year is a middle-of-the-road planning figure, with real quotes ranging from roughly 0.2% to over 1.5% for smaller down payments and weaker credit.

Two features of the month-by-month simulation deserve attention. First, PMI drop-off: because the threshold is 80% of the original price (for the standard calculation), steady payments alone eventually carry the balance below it — in the example below that takes about 8 years and 2 months. Home value appreciation can qualify you earlier through a new appraisal, and extra principal payments shorten the wait directly, since every extra dollar reduces the balance the threshold is compared against.

Second, total interest. On a 30-year loan at typical recent rates, total interest roughly equals the amount borrowed — you pay back about two dollars for every dollar lent. Shortening the term to 15 years typically cuts total interest by more than half while raising the payment by roughly 40–50%. Try both terms above and compare the 'total interest' line; it is the most honest single number in mortgage shopping.

Worked example

A $425,000 home with 10% down ($42,500), a $382,500 loan at 6.75% for 30 years, property tax of $5,100 a year, insurance of $1,800 a year, and PMI at 0.55% of the loan per year. The calculator is pre-loaded with these figures.

The headline number — $3,231.20 a month while PMI applies — is about 30% higher than the principal and interest alone. Buyers who budget only for P&I on this home would be short roughly $750 every single month. Note also the two quiet giants in the table: taxes and insurance together add $575 a month, every month, for as long as you own the home, and they generally rise over time even after the mortgage is gone.

And the total interest line deserves a pause: $510,619.58 of interest on a $382,500.00 loan. That is not a reason to avoid the mortgage — rent is not free either, and the loan buys a home — but it is a reason to treat the rate and term as six-figure decisions and to shop them accordingly.

PMI: what it is, what it costs, and how to get rid of it

Private mortgage insurance protects the lender if you default, and it is required on conventional loans when the down payment is under 20%. It buys you something real — the ability to buy sooner with less saved — but it is a pure cost: it builds no equity and protects you not at all. Typical pricing runs from about 0.2% of the loan per year for a 15–19% down payment with strong credit to 1.5% or more for 3–5% down with weaker credit. On the example loan, PMI at 0.55% costs about $175 a month.

PMI ends three ways. It cancels automatically when the balance reaches 78% of the original value on the original schedule. You can request cancellation at 80%. And you can often remove it earlier by refinancing or by documenting appreciation with a new appraisal once you have some payment history. Because PMI disappears at a known threshold, extra principal payments early in the loan do double duty: they cut interest and they shorten the PMI period. If you are near the 20% line, it is usually better to reach 20% down and skip PMI entirely than to buy sooner with 10–15% down.

Government loans differ: FHA charges an upfront premium plus annual mortgage insurance that often lasts the life of the loan, and VA loans use a funding fee instead of monthly insurance. If you are comparing loan programs, compare the full insurance cost, not just the rate.

30-year vs. 15-year mortgage

The 30-year term minimizes the payment; the 15-year term minimizes the cost. Lenders also price 15-year loans lower — often half a point or more below 30-year rates — which stacks the savings. On a $382,500 loan, a 15-year loan at 6.0% costs about $3,228 a month versus about $2,481 for 30 years at 6.75%, but total interest falls from roughly $511,000 to roughly $198,000. The shorter loan also builds equity far faster, which matters if you move within a decade: after seven years, the 15-year borrower owes dramatically less.

The catch is flexibility. The higher required payment is not optional in a bad month. A common middle path is a 30-year loan paid on a 15-year schedule voluntarily — you keep the contractual safety net and capture most of the interest savings while you are able. The loan payoff calculator shows exactly how a chosen extra payment reshapes a payoff date and interest total, and the same logic applies to a mortgage balance.

Related calculators

Frequently asked questions