is nit admission is based on category rank or air rank bcz they have given cut off for different category

It is based on AIR and do not get distracted by petty issues, just check out where do you stand – - in or out, if it is a green signal into IIT./NIT then it is quite good or thereis no dearth of qualitative colleges or universities. There are institutions which have earned IITs like stature in case of imparting qualiy education as well as sound placement graphs, you may try at – DIT uni, Dehradun,..........Lovely Professional uni, Phagwara,.............GITAM Uni, Vishakhapatnam