Mortgage Calculator

A mortgage calculator estimates the fixed monthly payment on a home loan from three inputs: the loan amount (principal), the annual interest rate, and the term in years. This free mortgage calculator uses the standard amortization formula, M = P x r x (1 + r)^n / ((1 + r)^n - 1), where r is the monthly rate (APR divided by 12) and n is the number of monthly payments. Because interest compounds monthly, the payment stays level while the split between principal and interest shifts over time. In the early years of a 30-year loan, the large majority of each payment is interest, which is why the amortization schedule is so revealing. The tool reports your monthly principal-and-interest figure, the total interest paid across the life of the loan, the total amount repaid, and a year-by-year breakdown. Adjust any input to compare scenarios instantly: a 15-year term roughly doubles the monthly payment but can cut lifetime interest by more than half, and a single percentage point of rate difference changes the total cost by tens of thousands of dollars on a large loan. One important caveat: this calculates principal and interest only. Property taxes, homeowners insurance, private mortgage insurance (PMI), and HOA fees are not included, so your true monthly housing cost (often called PITI) will be higher than the figure shown here. Everything runs locally in your browser, so the loan amounts and rates you model are never uploaded, logged, or shared. That makes it safe to run dozens of what-if scenarios on a sensitive budget before you ever talk to a lender, and to compare competing offers without leaving a trail of your finances on a third-party server.