The percentage of taxes taken out a paycheck depends heavily on the employee's federal, state and local tax brackets for income and filing status, as well as the employee's withholding declaration on the W-4 form, notes Sure Payroll. Furthermore, all employees also have to pay 6.2 percent for Social Security taxes and between 0.9 and 2.35 percent for Medicare taxes, as of 2015, notes the University of Texas at Austin.
The percentage of taxes withheld also depend on the employee's before-tax deductions, notes the University of Minnesota. These deductions reduce the employee's taxable income and can have an effect on either the state or federal taxes of the Medicare and Social Security taxes withheld. Websites like SurePayroll have online calculators that employees can use to estimate the amount of taxes withheld from their checks.