This entire thread was so helpful as I tried to confirm that Turbotax did the "maximize" correctly between employee and employer contribution. For anyone curious (and also for my own notes if I need to recreate this), to get the Employer contribution amount, look after the Schedule C; there might be the QBI Deduction Smart Worksheet and look for line 3 - Sch C profit (loss), then subtract 5b Total Deduction for 1/2 SE tax. Then multiply that amount by 20% per @dmertz and you'll arrive at the employer contribution. That plus your max employee contribution for that year (see IRS docs) plus any catch-up if you're over 50 yo, and that should equal what Turbotax calculates as "maximize." It seems like to get the super max contributions for 2023 of $76500 = $7500 catchup over 50yo + $22,500 employee contribution, therefore employer match would have to be $46,500 which means your business profit would need to be at least $232,500
