MusicBrainz API
MusicBrainz (musicbrainz.org) has 2 public methods: get artist by name and get song identifiers. Each costs 1 credit per completed run (1¢ with pay as you go); failed runs are free.
Unofficial. Not affiliated with or endorsed by MusicBrainz.
Methods
2Looks up an artist or band on MusicBrainz by name, optionally narrowed by country, and returns reference details, recorded members, aliases, genres and official links.
Returns name, type, country, home area, dates, members, aliases, genres, official links, MusicBrainz and ISNI/IPI ids
Readmusicbrainz.org/get_artistFinds the best-matching studio recording on MusicBrainz for a song title and artist. Returns its ISRCs, first release date and up to 25 of its earliest releases.
Returns title, artist, length, ISRCs, first release date, recording link, earliest releases
Readmusicbrainz.org/get_song_identifiers