A door closer is a mechanical device that closes a door, in general after someone opens it, or after it was automatically opened. Choosing a door closer can involve the consideration of a variety of criteria. In addition to the closer's performance in fire situations, other criteria may include resistance to opening forces (for use by disabled or infirm) as well as health, safety, durability, risk of vandalism/ligature and aesthetics.

There are four styles of interior door-closer:

Surface-mounted door closers come in four variations: slide-track arm, regular arm surface mounted, parallel arm surface mounted, and top jamb mounted. Overhead door closers are typically surface mounted, though most manufacturers offer concealed models too. Such closers mount inside a pocket in the door frame or are mounted in the floor directly under the pivot point and are completely concealed.

Another type of door closer, a surface mounted one, is attached to the door frame behind the door (where the hinges are) next to the middle hinge. The "arm" rests against the door, and a spring that is bent by the user opening the door closes the door by retracting to its proper shape.