Our verdict: Kid3 is a thorough, cross-platform tag editor that handles whole albums and almost every audio format. It is especially strong at converting between tags and filenames and at scripting. The Windows version ships as a ZIP without an installer, and the dense interface takes some learning.

About Kid3

Kid3 is an audio tagger developed by Urs Fleisch and hosted by KDE. It edits tags in MP3, Ogg/Vorbis, FLAC, MP4/AAC, Opus, WavPack, WMA, WAV, AIFF, Matroska and other formats, with full control over ID3v1 and ID3v2 tags.

It is built for tagging full albums without typing the same values again: set artist, album and year for all files at once, generate tags from filenames or filenames from tags, and import album data from MusicBrainz, Discogs and other sources. Tasks can be automated with QML/JavaScript or the kid3-cli command-line tool.

What it does well

Multi-file editing. Sets shared fields such as artist, album and year for a whole album in one step.
Tags and filenames. Generates tags from filenames and folder names, or renames files from tags.
Online album import. Imports album data from MusicBrainz, Discogs, gnudb.org and other sources.
ID3 control. Edits all ID3v2.3 and ID3v2.4 frames and converts between ID3 versions.
Automation. Scripts with QML/JavaScript and a command-line version, kid3-cli.

Who it is for

Good fit

People cleaning up large music collections, users of several operating systems, and anyone who wants to script tagging.

Look elsewhere

Users who want a simple installer and a minimal interface, or who only fix a tag now and then.

Pros and cons

Pros

Supports almost every audio format
Strong filename-to-tag conversion
MusicBrainz and Discogs import
Command-line and scripting support

Cons

No Windows installer, only a ZIP
Busy interface with many panels

How to install Kid3

The Windows download on kid3.kde.org is a 64-bit ZIP served through SourceForge; a separate Qt 5 build exists for Windows 7. Extract the ZIP to a folder such as C:\Tools\Kid3 and run kid3.exe; there is no installer and no Start menu entry until you create a shortcut. Back up files before the first bulk rename.