How much house can I afford is a home affordability calculator to estimate how much house can I afford. The home affordability calculator uses annual income and monthly debt to estimate how much mortgage can I afford and how much I can pay monthly. The how much house can I afford calculator includes options for taxes and insurance, and private mortgage insurance (PMI). When a borrower pays less than 20% for a down payment, they may have to pay for private mortgage insurance that most lenders require. If you are a first time home buyer, use this home buying calculator to estimate what kind of house that you can afford to buy. Based on the annual income and monthly debt, the home affordability calculator estimates how much can pay in monthly mortgage payments. This will determine how much house you can afford. Use the following table to estimate how much house and mortgage you can afford based on your annual income.