ID3 is a metadata format for MP3 audio files.
ID3 or ID-3 may also refer to: ID3 algorithm, an algorithm for constructing decision trees ID3 (gene), a human protein ID-3 format, a standard size for identification cards defined by ISO/IEC 7810 ID3, a post-dubstep/glitch artist Volkswagen ID.3, a battery electric car by the German manufacturer Volkswagen