Mp3tag is a powerful and easy-to-use tool used to edit the metadata of audio files. It supports batch tag-editing of ID3v1, ID3v2.3, ID3v2.4, iTunes MP4, WMA, Vorbis Comments and APE tags for multiple files at once, covering a variety of audio formats.
Furthermore, it supports online database lookups from Amazon, Discogs, MusicBrainz or freedb allowing you to automatically gather proper tags and download cover art for your music library.
You can rename files based on tag information, replace characters or words in tags and filenames, import / export tag information, create playlists and more.

Mp3tag Interface
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Screenshots
Export Configurations (customized reports)