MP3 tag editor. Without touching the audio.

At a glance

Why this is lossless

An MP3 file is two things stuck together: an ID3 tag at the front holding the metadata, and the audio frames after it. Players read the tag for the title and artwork, then decode the frames for the sound. The two are entirely independent.

That means editing tags does not require touching the audio at all. This tool parses the existing tag to fill in the form, builds a brand new tag from what you type, and writes it out followed by the original audio bytes, unmodified. The sound that comes out is bit-for-bit identical to the sound that went in.

This is worth stating because a lot of online "tag editors" decode and re-encode the file, which costs you a generation of quality for a change that should cost nothing. If a tag editor asks you to choose a bitrate, it is re-encoding, and you should not use it.

When you'd want this

• After converting a file. Every conversion on this site — and almost every converter anywhere — drops metadata, because the tagging systems of different formats do not map onto each other. Converting a FLAC album to MP3 gives you correctly named files with no tags at all. This is how you put them back.
• After splitting a long recording, where the pieces come out numbered but untitled and an audiobook needs chapter names.
• Fixing a badly tagged download — wrong artist, missing album, track numbers in the wrong order so an album plays shuffled.
• Adding cover art so a file shows something other than a grey placeholder in your music app or car display.
• Tagging your own recordings and mixes before sending them out, so they arrive looking finished.

Fields that matter, and why

Album artist is the one people miss. On a compilation, every track has a different artist, and music apps will split the album into a dozen one-track albums unless album artist is set consistently across all of them. Setting it to "Various Artists" — the same string on every track — keeps the album together.

Track number determines play order. Without it, most players fall back to alphabetical filenames, which is why albums so often play in the wrong sequence. Plain numbers work; "3/12" style is also valid and tells a player how many tracks to expect.

Year is used for sorting and for grouping by decade. It expects a four-digit year.

Artwork is embedded in the file rather than referenced, so it travels with it. Square images work best — most players crop to a square regardless — and there is no need for anything larger than about 1000 pixels, since a large image inflates every copy of the file.

Limits worth knowing

MP3 only. Other formats store metadata in entirely different structures: M4A and MP4 use atoms, FLAC and OGG use Vorbis comments, WAV has no widely agreed system at all. Handling those properly means a different parser for each, so this tool is scoped to ID3.

One file at a time. Tagging is per-file work by nature — the whole point is that each file gets different values — so there is no batch mode.

It writes ID3v2.3 rather than 2.4. 2.4 is newer and technically better, but its syncsafe frame sizes still confuse some car head units and older hardware players, which then show no tags at all. 2.3 is read correctly by essentially everything.

Existing tags are replaced rather than merged, so anything already in the file that this tool does not expose — lyrics, ratings, replay gain — is not carried across. For most files that is nothing; if you rely on those, use a dedicated desktop tagger.