AGI and tax bracket on IRS tax return ?

You aren't in "a single" tax bracket.

The US has a progressive tax system. 

You are taxed at the different tax brackets based on the income:

Tax rate    Married filing jointly or qualifying widow          

10%          $0 to $19,400         

12%          $19,401 to $78,950          

22%          $78,951 to $168,400          

24%          $168,401 to $321,450          

32%          $321,451 to $408,200          

35%          $408,201 to $612,350          

37%          $612,351 or more   

if you make $100000

$19400 is taxed at 10% = 1940

$59549 (this is the amount between $19401 to $78950) taxed at 12% = 7145.88

$21049 (this is the amount between $78951 to $100000) taxed at 22% = 4630.78

Total taxes = $13717 (taxes are rounded)

If you google "tax brackets 2020" you'll find many sites with the table of bracket vs. income. It sounds like what you really want to know is how much more income you can take before hitting the next bracket.

This one has a calculator where you type in your taxable income:

http://www.moneychimp.com/features/tax_brackets.ht...

Note that TAXABLE income is your total income minus deductions. And you should also leave out long-term capital gains and separately evaluate the effect on their tax rate.

Yes it absolutely WILL raise your income and it may indeed put you in a higher bracket when you withdraw money from your 401K.  You will immediately pay income tax on the money you take out and whatever sum you withdraw will be added to your gross income for both federal AND state returns. 

You can find tax tables online for most years. No, your return doesn't show your 'bracket'. But the bracket isn't the biggest issue. The gross income from all sources is a bigger issue for you. 

Not to mention the penalty for early withdrawal from your 401K if you're not at least 59-1/2 years old. 

Best check with your 401K manager and see what other penalties you may incur before making that withdrawal, such as not being able to contribute catch up funds, or state early-withdrawal penalties.  

AGI is not the issue.  Taxable income is the issue.  Taxable income is AGI after deductions, either standard or itemized.  After you have taxable income, you use the brackets shown by A Hunch.

Download the instruction book and check.

Look at what the brackets are and then look at your AGI and see what bracket it falls in.  Only the money above the bracket line is taxed at the higher amount, not all your money.

Tax rates are spelled out on the IRS web site. www.irs.gov