ISRC vs ISWC vs IPI: The Music Codes Every Songwriter Needs to Know

Behind every royalty payment is a trail of codes. Three of them cause most of the confusion for songwriters and independent artists: the ISRC, the ISWC and the IPI. They look like random strings of letters and numbers, but together they are how streaming services, societies and publishers work out which recording is which song and who should be paid. When these codes are missing or do not match, money gets stuck. This guide explains each one in plain English.

The short answer

• ISRC (International Standard Recording Code) identifies a recording.
• ISWC (International Standard Musical Work Code) identifies the song itself.
• IPI (Interested Party Information) identifies a person or company with a stake in the song.

What is an ISRC?

An ISRC is a unique code for one specific sound recording, like a fingerprint for the master. If you release a studio version, a live version and a remix, each gets its own ISRC. Your distributor or label normally assigns it when you release the track, and it stays with that recording for life. Streaming services use the ISRC to count plays and pay the owner of the master. You can find more about the ISRC system at the IFPI ISRC site.

What is an ISWC?

An ISWC identifies the composition: the melody and lyrics, regardless of who records it. It always begins with the letter T followed by digits. A song keeps the same ISWC no matter how many times it is recorded, covered or remixed. Societies use it to link all the recordings of a work to one registration, so the writers are paid correctly. The ISWC is allocated when a work is registered with a collecting society, and you can learn more at ISWC Net.

What is an IPI number?

An IPI number identifies a person or company: a songwriter, composer, lyricist or publisher. It is how societies tell apart two writers with the same name and make sure each one is paid for the right works. You normally receive an IPI number from your society when you join. Our guide to registering a song, IPI numbers and split sheets shows where it is used in practice.

What the codes look like

• ISRC: 12 characters in four parts: a two-letter country code, a three-character registrant code, a two-digit year and a five-digit designation number, for example GB-XXX-26-00001 (an example format, not a real code).
• ISWC: the letter T, nine digits and a check digit, for example T-123.456.789-0.
• IPI: a number of up to eleven digits assigned to the person or company, for example 00123456789.

You do not create these by hand. They are issued by your distributor, your society or the relevant agency, but you should know where to find them.

How the three codes fit together

Think of it as a chain:

1. A listener plays a recording. The platform reports its ISRC.
2. The ISRC is matched to a work with an ISWC.
3. The ISWC is linked to the writers and publishers through their IPI numbers and splits.
4. Money is divided and paid.

If any link in the chain is missing, the money can stall. This is one of the main reasons royalties become "unmatched" and sit in the pool we describe in black box royalties.

Covers, remixes and re-releases: what changes?

• A new recording of the same song (a cover, a live version, a re-record) gets a new ISRC but keeps the same ISWC, because the song has not changed.
• A remix is a new recording, so it gets its own ISRC. If it adds new melody or lyrics, it may also need its own work registration.
• A re-release of the same recording generally keeps its original ISRC. Only a genuinely new recording should receive a new one.
• A change of distributor should not change your ISRC. If it does, plays can be split across two codes and statements become hard to reconcile.

Other codes you will meet

Release-level codes such as the UPC or EAN barcode identify an album or single as a product, not a song or a recording. ISNI identifies public identities such as artists. They are useful, but they do not replace the ISRC, ISWC and IPI for royalty matching.

Why codes go wrong

• The recording was released but the work was never registered with a society.
• The title or spelling differs between the recording and the registration.
• A writer is missing or the splits do not add up to 100%.
• The same recording has been given more than one ISRC, or two different recordings share one.
• No publisher is attached, so the second half of the royalty has nowhere to go (see writer's share vs publisher's share).

Pre-release metadata checklist

1. Every recording has its own ISRC, assigned once and never reused.
2. The song is registered with your society, so it has an ISWC.
3. Every writer has an IPI number on the registration.
4. The splits add up to 100% and match your split sheet.
5. The title and writer names are identical everywhere.
6. A publisher is named, so both shares of the royalty can be paid.

How to find your own codes

Your ISRCs are on your distributor's release pages. Your ISWCs and IPI number are in your society's member area, for example under your registered works. If your catalogue is large or messy, a publishing administrator can audit it, fix mismatches and register the rest. Dark Lab Records Publishing manages composition registration, writer and rights data and statement reporting in one dashboard, and you keep 100% of your copyright. See how it works, or read more about choosing a publishing administrator.

Final thoughts

You do not need to memorise the codes, but you should know what each one does and check that they exist for every song you release. Get the registrations right before release day and the money has a clear path to you. If you suspect songs are unmatched, start by looking up your works and compare titles, writers and splits against your split sheet.