Abstract: A door operating apparatus for use with a door pivotably mounted to a door frame permits the door to swing in one of a manual operation and an automatic operation. The apparatus includes a housing, a first rotatable sprocket disposed in the housing and coupled to the door, a second rotatable sprocket disposed in the housing and connected to the first rotatable sprocket by a roller chain, the second sprocket having a top face with a protrusion, a drive assembly disposed in the housing and having a motor operably connected to a drive arm. A force applied to the door permits the first and second sprockets to rotate simultaneously to enable the door to swing open. Activation of the motor allows the drive arm to contact the protrusion and drive the second sprocket, thereby rotating the first and second sprockets simultaneously to enable the door to swing open.