Please clarify your question.
Unfortunately, we can't see your screen to see where you are, so I'll have to ask you a couple of questions.
Calculating 401-K withholdings is not within the scope for TurboTax, but these are factors to consider.
These are all factors that contribute to the question you asked.
I'll hazard a "simplistic" answer...and only for a traditional 401k, not a Roth 401k.
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IF your income for the year puts you entirely in the following ~tax brackets, you would have to put the following approx. amounts in over the full year of 2024 (total, not monthly) to eliminate ~$7,000 in Federal taxes.
Bracket | Amount int 401k (not exact)
10% ~70,000 (yeah, this is not possible)
24% ~29,200 (over the 23,000 max, unless age 50+)
32% ~21,800
35% ~20,000
But you get the idea.