To calculate your monthly payment, use our free mortgage calculator to find out which home loan monthly payment options fit your goals best.  See how your monthly payment varies based on the purchase price, down payment, loan term, and interest rate. Calculating your monthly house payment is an important step in determining how much house you can afford. When buying a home or refinancing, you can use Sun American’s free mortgage calculator anytime to estimate your monthly payment. If you have any questions, click on the “Get a Free Quote” to get in contact with a Loan Officer.