An International Standard Musical Work Code (ISWC) is the global standard for identifying unique musical works. Much like the ISRCs that signify distinct recordings, each ISWC should only be used once. Any alternate translations, arrangements, and adaptations of a song should be registered separately and receive their own one-of-a-kind code.

Here is an example of what an ISWC might look like: T-123-456-789-0. Performing Rights Organisations (PROs) assign these codes whenever a song is registered by a publisher or a publishing administrator like Songtrust. They include such critical details as a song’s title, writer(s), publisher(s) and splits.

If your work is already registered, its ISWC should be searchable through your PRO’s song archive. For more on how PROs work, check out our blog post here. To learn more about the difference between an ISRC and ISWC, check out this article.