Originally Posted by BigJosh
I believe they are similar.
My understanding is that an inverted row involves the feet being straight out on the floor (heels down, toes facing ceiling), and the upper body close to parallel to the floor, chest facing up towards ceiling, back towards ground. This creates a pull on the horizontal plane.
Rack chins on the other hand, involve the feet being up on a bench and the upper body being more upright or perpindicular to the ground. This creates a pull in the vertical plane.
Oh right, that's probably part of the confusion for me; I've seen inverted rows with progressions which go from floor to bench and above etc but never heard the term rack chins.