Mortgage calculators are handheld devices much like ordinary mathematical calculators. They are specially programmed to compute values relating to mortgages, such as interest rates, amortizations and monthly payments.

Mortgage calculators are very useful tools to check whether the user is qualified to obtain a loan. They work for conventional loans as well as loans insured by the Federal Housing Administration (FHA) or the Veterans Administration (VA). Mortgage calculators can compute the total payment including principal, interest, taxes and insurance, called as the PITI payment. Payments can be calculated irrespective of the time period how it is paid