Common Works Registration · 2.1 / 2.2
Upload a CWR file.
We’ll tell you if the format is broken, and about your writers and songs.
A file can pass every format check and still not match how its writers are registered, or carry songs a society will reject. CWR Check reads all of it. Free, no signup, and nothing you upload is stored.
1 · Is the format right?
Every record, share and control total against the CISAC CWR spec, each problem pointed at its exact line: the rejections a society would send back, before you deliver.
2 · Do your writers match their registrations?
Every writer cross-checked by Songlinks against public registration data: the name as registered, the IPI, and how many of their works are registered under another spelling or IPI.
3 · What’s wrong with your songs?
Every song, one by one: its chain of title, shares that add up, publisher caps, ISWC check digits and duplicate work numbers. Add a society’s acknowledgement file to see which songs it rejected.
Drag and drop a CWR file
.V21 · .V22 · up to 20 files, 10 MB each — about 12,000 songs per file
Files are validated in memory and never stored — unless you ask for a share link. The writer check sends the file’s writer IPI name numbers to Songlinks and nothing else; you can turn it off in the report.
Every CWR file names its writers and their IPI name numbers. Songlinks, our songwriter lookup, checks each number against public registration data and tells you what differs — not who is wrong.
What it finds
Works registered under a spelling or IPI name number other than the writer’s main one. Royalties follow the registration a work is filed under, so those works may not reach the writer where they expect. Also a name spelled differently from its registration, a number nobody holds, and a number several people share.
What it sends
Only the writers’ IPI name numbers, at most 200 per file — never titles, names or shares. Turn it off in the report and it stays off.
What you get
A summary at the top of the report’s Writers section, each writer’s detail in a panel beside the report, and a next step: see where works are registered, have us correct them, or save your writers to a free catalogue.
How writer registrations drift apart → · What an IPI name number is →
Your works already live somewhere — an admin system, a database, a spreadsheet export. Getting them out as compliant CWR is the painful part. Send us the data as JSON and download a delivery-ready CWR 2.1 or 2.2 file — every prefix, sequence number, and control total handled. If the free check passes, your download is guaranteed to validate.
- Export your worksOne JSON file from whatever holds your catalog — see the shape or wire up the API.
- Check it — freeWe build your file and prove it validates. No signup, nothing stored.
- DownloadFree while we’re in open beta — regenerate as often as you like.
Administrators: tag each catalog with a
client label to keep client catalogs separate. Volume
or SLA questions:
alex@kanetechgroup.com.
Kane Technology Group · Est. New York · Twelve years of registration at scale
The tools above are for people who deliver their own files. If you’d rather hand the whole thing off — setup, delivery, acknowledgement chasing, corrections, every society — that’s what we do for a living. CWR Check is built by Kane Tech Group, which has been delivering registrations at scale for twelve years: catalogs from a few hundred works to millions, to societies worldwide. Tell us about yours and we’ll take it from there.
Coming from Music Maestro or Curve? We know both roads well: we’ve exported catalog data straight out of each and delivered society-ready CWR built from it — works, splits, agreements, territories and all. Whether you’re staying put or migrating, your registrations don’t have to wait. CWR from Music Maestro → · CWR from Curve →
Parsing
Every record is read against the official CISAC field tables (CWR19-1070R1) — including the trimmed lines and version quirks real-world files actually have.
Spec violations
Structure, control totals, sequence numbers, mandatory fields, share ranges — the exact rejections a society would send back, caught before you deliver.
Anomalies
Shares that don’t add up, unknown record types, filenames off convention — the things societies tolerate but a careful registrant fixes. Flagged as warnings, kept apart from hard errors.
The full picture
A line-by-line report of every work, every chain of title, every share — open it, download it, or share it with a link. Your file stays yours.
What is a CWR file?
CWR (Common Works Registration) is the CISAC standard format
publishers use to register musical works with collecting societies
such as ASCAP, BMI, SESAC, GEMA, PRS, and the MLC. A CWR file is a
fixed-width text file — usually with a .V21 or
.V22 extension — carrying works, writers,
publishers, ownership shares, and collection territories in a
strictly defined record layout.
What does the writer check look for?
For each writer with a valid IPI name number, Songlinks looks the number up in public registration data and reports what differs: works registered under a spelling or IPI name number other than the writer's main one (royalties follow the registration, so those may not reach the writer where they expect), a name spelled differently from how it is registered, a number no registration carries, and a number held by several people. It says what differs, never who is wrong: the registration can be the one that is off. Only IPI name numbers are sent, and the report has a switch to turn the check off.
Why was my CWR file rejected by a society?
Nine times out of ten it isn’t your data — it’s the bookkeeping. CWR is a fixed-width format, and societies bounce files over details no human would spot:
- a record sequence number that skips by one
- a GRT or TRL control total that’s off because a record was added late
- one blank mandatory field on one work
- shares totalling 99.98% instead of 100%
- a publisher claiming more than the 50% performing-rights maximum
Any one of these can reject a transaction — or the whole file — and you often find out weeks after delivery, at the cost of a full registration cycle. CWR Check runs those same checks in seconds and points at the exact line, so the file that goes out is the file that gets accepted. Deeper dive: why CWR files get rejected.
Which CWR versions are supported?
CWR 2.1 and CWR 2.2 — the versions societies accept in production today — including registrations (NWR/REV), agreements (AGR), acknowledgements (ACK), and the non-Roman alphabet record types. Record layouts follow the CISAC functional specification CWR19-1070R1. (CWR 3.x exists on paper; production acceptance worldwide is still 2.1/2.2.)
Who takes what: ASCAP, BMI, and SOCAN receive CWR through MusicMark; PRS, GEMA, and STIM share the ICE works database; most European societies (SACEM, SIAE, SGAE, BUMA/STEMRA, SUISA and more) and agencies like The MLC and CMRRA take CWR directly; and across Asia and Latin America — JASRAC, NexTone, KOMCA, KOSCAP, SACM, UBC/Abramus — your local sub-publisher usually registers from your CWR. The full routing map, society by society: which societies accept CWR.
Is there a size limit?
Files up to 10 MB — about 12,000 song registrations — validate right here in seconds. If your catalog is bigger than that, please don’t try to squeeze a million rows through a browser: that’s pipeline territory, and building those is exactly what we do. Tell us about your catalog and we’ll spec it together.
Is my catalog stored anywhere?
Not unless you ask. Files are validated in memory and discarded when the response is sent; reports are built in your browser and exist only there. The one exception is explicit: if you click “Create share link”, that report — which includes your file’s contents — is stored at an unguessable URL and deleted after 30 days. Page views and site usage are measured with Google Analytics, which sets cookies in your browser; it never sees your file. Writers in a report link to Songlinks, our songwriter lookup, and the results offer to check the file’s writers there. When a report opens, it sends the writer IPI name numbers in the file (up to 200) to Songlinks to show how each writer is registered; you can turn this off in the report, and it stays off. Checking a JSON catalog does the same with the writers in the catalog, under the same switch. A writer’s link sends that writer’s IPI name number, or their name when the file has no usable number, only if you click it. Nothing else from the file is sent.
Can I create a CWR file without CWR software?
Yes — if your works are in any structured form. Export them from whatever system holds them — an admin platform, a database, a spreadsheet — into our JSON shape and the documented API (or the upload above) turns them into a delivery-ready CWR file: every prefix, sequence number, and control total handled, output guaranteed to pass the validator. The whole flow is free while we’re in open beta.
What is the difference between CWR 2.1 and 2.2?
CWR 2.2 adds fields to existing records — recording titles, display artists, ISRC validity on REC records; software package details on the transmission header; V-ISAN and EIDR identifiers on work origin — and introduces the explicit publisher-chain reference on PWR records. Most societies accept both; some still prefer 2.1.