A standard deduction is a level amount that applies to all knowledgeable taxpayers, regardless of the number of exceptions claimed on your tax return. It reduces your taxable income and indicates how much you may effectively deduct from tax for each exemption on which you qualify. There are two kinds of standard deductions available. The first is the “regular standard deduction,” based on filing status and making adjustments for age and blindness. The second is the “itemized standard deduction,” based on certain expenses paid during the year, such as medical costs and mortgage interest.