What is total percentage of income that will be withheld from an employee's paycheck for social security and medicare taxes?

The total percentage of income withheld from an employee's paycheck for Social Security and Medicare taxes is 7.65%. This includes 6.2% for Social Security on earnings up to a certain limit and 1.45% for Medicare with no earnings cap. High earners may also be subject to an additional 0.9% Medicare tax on income above a certain threshold. Therefore, in total, employees typically see a withholding of 7.65% for these taxes.