Users can estimate the financial ramifications of changes in one or more mortgage financing factors by using computerized mortgage calculators. Mortgage calculators are used by consumers to estimate monthly payments and by mortgage lenders to determine the financial appropriateness of a home loan applicant.

Principal, balance, interest compounded on a periodic basis, number of payments per year, the total number of payments, and amount of regular payments all go into the mortgage calculation. For example, more advanced mortgage calculators might factor in other costs such as state and municipal taxes and insurance premiums.