This article explains the difference between ISRC and ISWC and where to get the right codes for your music.
ISWC stands for International Standard Musical Work Code.
It serves to identify individual musical works.
More info on ISWC: https://www.iswc.org
ISRC stands for International Standard Recording Code.
It serves to identify individual sound recordings.
More info on ISRC: http://isrc.ifpi.org
Your distributor will assign an ISRC.
And your PRO will assign an ISWC.
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