How to Use
Enter the home price - the full purchase price, not the loan amount.
Enter your down payment as a dollar amount or percentage. A 20% down payment eliminates PMI.
Enter the annual interest rate. Use your lender's quoted rate or a current market benchmark.
Choose your loan term: 30 years for lower payments, 15 years for less total interest.
Instantly view your monthly P&I payment, total interest, and full amortization schedule.
Add estimated property taxes, insurance, and PMI to the result to get your true monthly housing cost.
What Is This Tool?
A mortgage calculator estimates your monthly principal and interest payment based on the loan amount, interest rate, and loan term. Monthly payments are computed using the standard amortization formula, which keeps your payment flat while shifting the ratio from mostly-interest in early years to mostly-principal later. What this calculator does not include is your total monthly housing cost: property taxes, homeowner's insurance, and - if your down payment is under 20% - Private Mortgage Insurance (PMI). These extras can add $400–$800 or more per month depending on your market and home price. Always budget for the full payment, not just principal and interest, to avoid being caught short after closing.
Why It Matters
A 0.5% difference in interest rate can cost or save tens of thousands of dollars over a 30-year loan. Running multiple scenarios - different rates, terms, and down payments - before making an offer gives you negotiating leverage and protects you from overextending. Many buyers focus on the monthly payment without seeing the total interest: a $400,000 home at 7% for 30 years costs over $558,000 in interest alone. Understanding the full picture helps you choose the right loan product, decide whether a larger down payment is worth delaying your purchase, and recognize when a 15-year loan is actually affordable for your budget.