Some mastering websites will ask you to provide ISRC codes for the music you send them to be mastered. You may be wondering what in the world an ISRC is…
ISRC stands for International Standard Recording Code. It’s a unique code assigned to a sound recording that identifies it for various purposes, such as tracking royalties from digital downloads. The code, described as a “digital fingerprint” from the ISRC website, is attached to a sound recording across all mediums. For example, the same ISRC code would identify the recording of a song whether it’s an MP3 file or on an audio CD.
A mastering engineer may ask for these codes to embed into your recordings during the mastering process, but it is usually not something you are required to have in order to get your songs mastered.
If you would like to apply to obtain your own ISRC codes for your songs, visit the RIAA website.