Here's some math...........
You pay 2 different taxes. The regular income tax and the SE tax. The 1/2 of SE tax on line 8a and the personal 12,200 Standard Deduction line 9 and the QBI line 10 are only deducted from your income for the regular income tax.
The Self Employment tax on line 15 is 15.3% on 92.35% of your Net Profit.
63,000 x .9235 = 58,180.50
58,180.50 x .153 = 8,902 SE TAX
This only gave me a QBI deduction on line 10 of $9,270 instead of 20%. Looks like you have to deduct the 1/2 SE tax from your Net Profit (63,000-4,451) plus some other limitation.
