It depends on your marital status, other income, exemptions, deductions, and credits.
Try this calculator:
http://www.dinkytown.net/java/Tax1040.html
What federal income tax percent should my employer deduct from my wages
You should get the information from your employer payroll department if you really need to know the correct numbers or amount that should be deducted from your gross earnings
These are the tex tables that show how much federal tax in 2012 you should pay relative to your income. These taxes are based upon your income and filing status
Percentage of business income should not be used to decide rent. Business needs and desires should be used to calculate rent. You could be making hundreds of thousands of dollars working out of a home office.
according to federal law all income should be reported from all sources
What federal income tax percent should my employer deduct from my wages
Always contribute what your employer will match, but consider contributing up to 10% of your income if you can afford it.
25
About 4% of your net annual income.
Salary
7%
You should get the information from your employer payroll department if you really need to know the correct numbers or amount that should be deducted from your gross earnings
(20-25)%
The general rule is you should spend no more than half of your income on rent. The better you are doing financially, the smaller percentage of income goes towards your house/apartment.
Each state and organization will have its own criteria, from a fixed amount to a percentage of income. Percentage of income usually is between 25-30%.
50%
Rent shouldn't be than one quarter of your income.