lipsyncing

Lip-syncing, or lip-sync, is the act of moving the lips in time with a pre-recorded vocal track or a live voice so that the words appear to be spoken or sung by the performer. It is used in music performances, film and television production, theater, and animation.

In live performances, artists may lip-sync to a pre-recorded track to maintain vocal quality while executing complex choreography, staging, or stunts. It can be an artistic choice or a practical solution when singing live is difficult. Audiences’ reception of lip-syncing often depends on context, expectations, and transparency about the performance.

In film and television, lip-syncing appears in post-production dubbing and ADR to match dialogue to on-screen mouths and expressions, as well as in cases where productions require multiple language versions or unusable original audio. In animation, mouth shapes are synced to phonemes through lip-sync animation to produce believable dialogue and expressiveness.

Technical challenges include precise timing, phoneme accuracy, and natural facial movement. Approaches range from manual animation and motion capture to automated, speech-driven algorithms, and to playback-based alignment in live performance.

Controversies have arisen when audiences believe performers are singing live when they are not. A notable example is the Milli Vanilli case in the late 1980s and early 1990s, which highlighted issues of authenticity and presentation in staged performances.