哪国的法律，要付40%的税？在开玩笑吧？

ever heard of itemized deductions or personal exemption?

for a family of 4 with 100k pretax income, you can have $12800 for personal exemptions and $10000 standard deduction. this will bring your taxable income down to $77200. the federal tax is about $12630.

however, for this type of family, it is likely to have a private home with a mortgage and retirement savings.

for mortgage saving, it is likely the mortgage interest and property tax will be $20000. if you save another $15000 for the retirement (thru 401k and/or roth IRA), it will bring your taxable income down to $52200. then, the federal tax is only about $7100.

where did you get the idea that the tax is $40k from $100k income?