The amount of tax withheld from your pay depends on what you earn each pay period. It also depends on what information you gave your employer on Form W-4 when you started working. This information, like your filing status, can affect the tax rate used to calculate your withholding. Since the exact amount that is withheld from your pay can change with each paycheck, the easiest way to figure out your tax withholding is by estimating it. See the IRS Tax Withholding for Individuals page to:
Know when to check your withholding
Use the withholding estimator tool to estimate your tax withholding