I always thought that The exorcist was the scariest movie to me, until i saw Friday the 13th on Saturday.

on the basis of different type of Horror Genre my scariest movies are-

Torture- A’linteriur AKA Inside,Saw,Hostel
Atmospheric-Blair witch project
Clusteropheobic-The Thing,Cube
Video nasty-Evil dead 1
Italian-Demons
Zombie-Living dead series
Slasher-Friday the 13th series,wrong turn:dead end,Haute tension
Vampire-Salems Lot
Gorefest-Dead alive
vodoo-Exorcist