Enter a home price, down payment and rate to see your full monthly mortgage payment — principal and interest plus property tax, homeowners insurance, PMI and HOA dues — and how much interest you will pay over the life of the loan. How the monthly payment is calculated Principal and interest use the standard amortization formula: M = P × r(1+r) n / ((1+r) n − 1) , where P is the loan amount, r the monthly rate (APR ÷ 12) and n the number of payments. Property tax, insurance, PMI and HOA are then added on top, because most lenders collect them in the same monthly bill through escrow. Monthly payment by home price 20% down, 6.25% fixed for 30 years, 1.1% property tax and $1,800/yr insurance. Home price Loan amount Principal & interest Total monthly Total interest $300,000 $240,000 $1,477.72 $1,902.72 $291,980 $400,000 $320,000 $1,970.30 $2,486.96 $389,306 $500,000 $400,000 $2,462.87 $3,071.20 $486,633 $750,000 $600,000 $3,694.30 $4,531.80 $729,9...