Mp3tag
Free
Mp3tag is a tool to edit metadata of audio files.
MusicBrainz Picard
Open Source
MusicBrainz Picard is a free and open-source software application for identifying, tagging, and organising digital audio recordings.
EasyTAG
Open Source
EasyTag (EasyTAG) is a graphical tag editor for Linux and Microsoft Windows.
taghycardia
Free
taghycardia is a free program for automated MP3 cover art downloading and tag fixing.
MediaMonkey
Freemium
MediaMonkey is a music manager and music player for serious music collectors.
TagScanner
Free
TagScanner is a powerful tool for organizing and managing your music collection.
TuneUp
Commercial
TuneUp will fix mislabeled songs, add missing cover art and remove duplicate tracks
Compare Kid3 with alternatives
Compare MusicBrainz Picard and Kid3 and decide which is most suitable for you.