Musicbrainz Picard if you like graphical interfaces.
Beets if you like the command line.
Who are we?
We are digital librarians. Among us are represented the various reasons to keep data -- legal requirements, competitive requirements, uncertainty of permanence of cloud services, distaste for transmitting your data externally (e.g. government or corporate espionage), cultural and familial archivists, internet collapse preppers, and people who do it themselves so they're sure it's done right. Everyone has their reasons for curating the data they have decided to keep (either forever or For A Damn Long Time). Along the way we have sought out like-minded individuals to exchange strategies, war stories, and cautionary tales of failures.
We are one. We are legion. And we're trying really hard not to forget.
-- 5-4-3-2-1-bang from this thread
Musicbrainz Picard if you like graphical interfaces.
Beets if you like the command line.
https://www.mp3tag.de/en/ could be useful if your files are already uniformly named and if you're on Windows
Or if you want to edit multiple files in the same way simultaneously (e.g. adjust album or artist name)
Yeah that one is very good.
If you just want correct metadata (no own adjustments), then getting it from the MusicBrainz database is probably easiest. You can use MusicBrainz Picard for that: https://picard.musicbrainz.org
It does also seem to have a scripting API. No idea how well that works, though.
This looks nice, thanks!
Ive used easytag in the past.
There's also KID3 and Foobar2000.
+1 for kid3
I do it in Winamp, but you probably just want a dedicated software like the other commenters proposed