Squat Depth Diagnostics

Does everyone need to squat?

Yes.

Does everyone need to squat to the same depth?

No.

But how do you figure out what is the safest maximum depth someone should go down to in a squat?

Tony Gentilcore has a really excellent article on that subject on T-Nation:

Does Everyone Need to Squat Deep?

Scroll down for the video of the kneeling rockback assessment. You'll need someone to watch you, but you can see where the safe maximum depth of your squat is.