Red dot sights place the target and the reticle on nearly the same optical plane, allowing a single point of focus. This makes them fast acquisition and easy to use sights, allowing the user to keep their attention on the field of view in front of them. They are common in speed shooting sports such as IPSC. Military units and police forces have also adopted them. Red dot sights are also popular among paintball and airsoft players for similar reasons.

Because there is no magnification, the shooter need not worry about parallax or eye relief. The long eye relief makes red dot sights appropriate for firearms with heavy recoil that might drive a conventional short eye relief telescopic sight into the shooter's eye. Since dot sights can be mounted at any distance from the shooter's eye with no issues of focus, military rifle mounts usually place the sight in any mechanically-convenient mounting position, such as the carrying handle of the M16 rifle, or on a rail system (typically a Picatinny rail) on top of the rifle. This leaves plenty of room for night vision equipment to be used with the red dot sight.

Miniature red dot sights are becoming increasingly popular for use on pistols, both for competition and military applications