Congratulations on your retirement!
If you are withdrawing money from savings (not a retirement account), there is no set amount of withdrawals that will directly impact your tax liability. Any withdrawals from a 401(k) would be taxed at your ordinary income tax rate, based on the current IRS tax brackets.
Your taxable income can be projected by identifying your gross income (e.g. interest and dividends, withdrawals from retirement accounts) and then subtracting the standard deduction, which is currently $13,850 for a single filer under the age of 65.
Current tax brackets and standard deduction amounts can be found on the IRS website.
