on par (with someone or something)
Approximately equal (in some characteristic) to someone or something else. The two rival tennis players have been on par for the last seven years, constantly battling back and forth for dominance in the league. This is about on par with what I expected from their legal team. I have to say, their latest product isn't on par with their last one.
on par (with someone or something)
equal to someone or something. Your effort is simply not on par with what's expected from you. These two departments are right on par in productivity.