A cue mark, also known as a cue dot, a cue blip, a changeover cue or simply a cue, is a visual indicator used with motion picture film prints, usually placed in the upper right corner of a filmframe. Cue dots are also used as a visual form of signalling on television broadcasts.

A pair of cue marks is used to signal the projectionist that a particular reel of a movie is ending, as most movies presented on film come to theaters on several reels of film lasting about 14 to 20 minutes each (the positive print rolls themselves are either 1,000 feet or, more commonly, 2,000 feet, nominally 11.11 or 22.22 minutes, absolute maximum, with more commonly an editorial maximum of 9 to 10 or 18 to 20 minutes). The marks appear in the last seconds of each reel; the first mark, known as the motor cue, is placed about 8 seconds before the end of the picture section of the reel. The second mark, known as the changeover cue, is placed about 1 second before the end. Each mark lasts for precisely 4 frames (0.17 seconds).

Coded anti-piracy is a different kind of mark, used for watermarking to detect and prevent copyright infringement.