Mortgage Payment Calculator

Principal and interest stay fixed on a standard loan, while taxes and insurance usually drift upward over time.

PMI generally falls away once the loan balance reaches roughly 80% of the property value.

Principal and interest (P&I) is calculated using the standard loan amortization formula, based on the loan amount, annual interest rate, and loan term in years. This payment stays fixed for the life of a standard fixed-rate loan.

The calculator then adds one-twelfth of the annual property tax, one-twelfth of the annual insurance premium, and any monthly PMI (private mortgage insurance) to P&I, producing the total PITI payment. PMI generally applies when the down payment is below 20% of the property's value and typically falls away once the loan balance drops to roughly 80% of the property's value.

A first-year amortization breakdown shows how much of each month's payment goes toward principal versus interest, along with the remaining balance after 12 months. Early in a loan, interest makes up the larger share of each payment, and that split gradually shifts toward principal over time.

A borrower takes out a $320,000 loan at 6.5% for 30 years, with $4,200 in annual property tax and $1,600 in annual insurance, and no PMI. The monthly P&I payment is about $2,022.62.

Adding $350 for tax ($4,200 / 12) and $133.33 for insurance ($1,600 / 12) brings the total PITI payment to roughly $2,505.95 a month. Over the full 30-year term, total interest paid comes to about $408,143, illustrating how much of the loan's total cost is interest rather than principal. That total interest figure is roughly 1.28 times the original loan amount, a reminder that a 30-year fixed-rate loan typically costs more in interest than the principal borrowed. Switching to a 15-year term at a lower rate would raise the monthly P&I payment but substantially cut total interest paid over the life of the loan.