Turbo Tax Basic Tax Rate Calculation Check

I entered several Income numbers on a W2 to compare TurboTax output to Smart Asset and an excel function I wrote.  Smart Asset and my numbers always match, but TurboTax is off by some number of dollars.

Does anyone know why?  I did a similar test last year and recall getting similar deviations.  Didn't follow-up at that time.

One of the numbers is correct, the last one.  It is a different tax rate though.

Thanks,
Greg