There is no standard formula, it depends on your taxes and other deductions taken, which vary from individual to individual. Taxes vary by region, filing status and withholding allowances. Deductions include retirement contributions, union dues, insurance payments, student loan payments, child support, or others depending on yoru situation. You can do a google search for "pay calculator" or "net salaray calculator" and look at the ones that come up. I can't find something specific to my area (including taxes from the city, county and state as well as federal) but they can be helpful if you want to estimate. Also, paystubs include an itemized listing of deductions, so you can see you net and gross for a current job on your paystub.
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