You want to buy a $350,000 house with a 20% down payment. Your question is: What will my monthly mortgage payment actually be? You know the price, you know your down payment amount, but calculating the actual monthly payment involves complex formulas with principal, interest, taxes, and insurance. You could calculate it manually. You would need to use the amortization formula with logarithms, then add property taxes and insurance estimates. It requires multiple steps and financial knowledge. Or you could use a mortgage calculator to instantly show your monthly payment will be approximately $2,245 for a $280,000 loan at 6.5% interest over 30 years, including estimated taxes and insurance. A mortgage calculator estimates your monthly home loan payment by calculating principal and interest using the loan amount, interest rate, and term, then adding property taxes, homeowners insurance, and mortgage insurance if applicable. Mortgage calculators are used by homebuyers planning budgets, rea...