Examples
Worked examples
- Is an instance
https://w3id.org/dpv for the Data Privacy Vocabulary.
- Is an instance
https://w3id.org/fair/principles for the FAIR Guiding Principles statement.
Counter-examples
Looks similar, but isn't
- Not an instance
A vocabulary served directly from a researcher's personal website is not a w3id.org PURL.
- Not an instance
An identifier under purl.archive.org is a different PURL service, not w3id.org.
Editorial commentary
w3id.org is a free, community-run PURL service intended for Web vocabularies, ontologies, and standards. Each namespace is administered through pull requests to a public GitHub repository; redirect rules are expressed in Apache rewrite syntax and reviewed by the community group. The service deliberately stays out of content hosting — it only redirects — and is widely used by the linked-data and FAIR-data communities to provide stable identifiers for ontologies that may be hosted on personal or institutional servers today and elsewhere tomorrow.
References
- W3C Permanent Identifier Community Group, 'w3id.org' (w3id.org and github.com/perma-id/w3id.org).
Also known as
w3id
Machine-readable encodings
Use in your systems
<role vocab="credit"
vocab-identifier="https://casrai.org/dictionary/"
vocab-term="w3id.org PURL"
vocab-term-identifier="https://casrai.org/dictionary/term/w3id-purl" />{
"@context": "https://schema.org",
"@type": "DefinedTerm",
"@id": "https://casrai.org/dictionary/term/w3id-purl",
"name": "w3id.org PURL",
"identifier": "https://casrai.org/dictionary/term/w3id-purl",
"description": "A persistent URL hosted on the w3id.org domain by the W3C Permanent Identifier Community Group, providing a community-maintained redirect under https://w3id.org/ to ontologies, vocabularies, and standards documents that may move between hosting providers over time.",
"inDefinedTermSet": "https://casrai.org/dictionary/domain/persistent-identifiers#set",
"url": "https://casrai.org/dictionary/term/w3id-purl",
"sameAs": [
"w3id"
],
"license": "https://creativecommons.org/licenses/by/4.0/",
"publisher": {
"@id": "https://casrai.org/#organization"
},
"author": {
"@id": "https://casrai.org/#editorial-team"
},
"datePublished": "2026-05-21T02:10:57",
"dateModified": "2026-07-10T02:06:20",
"inLanguage": "en-GB",
"isAccessibleForFree": true
}
