Sync or synch may refer to:
- DIN sync, a standard interface for electronic music instruments
- File synchronization or syncing, to synchronize directories or files on computers
- Ford Sync, an in-car communications and entertainment system
- Oscillator sync, where a slave oscillator is reset by a master oscillator
- Samsung SGH-A707 or AT&T SYNC, a mobile phone
- sync (Unix), a command for Unix-like operating systems
- Sync, a signal used in composite video systems to coordinate the timings of lines, fields and frames
- Sync, an enemy character in Tales of the Abyss
- Synch (comics), a Marvel Comics superhero character
- Synchronization, the coordination of events to keep them in time
- SyncToy, a Microsoft PowerToy's software for file synchronization
- Synch (band), 1980s band who performed "Where Are You Now"
- Sync (2010), a video installation by Max Hattler
- Sync (street artist), a street artist operating out of Melbourne, Australia
- Synchronization rights, defined by a synchronization license, an example of music licensing
- Firefox Sync, originally branded Mozilla Weave, allows users to partially synchronize bookmarks, browsing history, preferences, passwords, filled forms, Add-ons and the last 25 opened tabs across multiple computers.