According to the latest year tax bracket, assuming your yearly income is 120,000, you fall into the 28% tax bracket for federal tax. Additionally, you may have to pay another 9% state tax (depend on where you live) before any deductible. Also, add on to that Social Security, Medicare etc you will pay close to 40% of your total income.
Now, when you take into account all of the tax deductible, you will probably pay anywhere from 35-38% of your total income (including state income tax on top of federal income tax). There is an alternative minimum income tax that prevents you from paying less than a certain amount of tax (this applies to people who have a lot of tax deductibles).
Assuming best case scenario, you only pay 35% of your total income to federal and state tax, social security, medicare etc (after deductibles) you have 65% of your income left to spend, and thats $78000, which is about $6.5k a month. Thats about enough to pay for a mortage, car, student loan and other expenses.
You won't get rich, but you will be able to live comfortably.
