I am calculating my underpayment penalty (I was unfortunately unaware that I was supposed to pay quarterly taxes from my small business income), and I am on "Tax Withholding by Quarter," where I enter my tax withholdings per quarter. It says "the total withholding you enter below must equal X" However, X is quite a bit more than what I actually had withheld for federal, and less than what I had withheld for federal + state. Where did this number come from? I have good data and can enter the quarterly withholdings, but the sum will not align with X.
