Researcher Identifier

A persistent, unique digital identifier assigned to an individual person -- as distinct from an identifier for a work, an institution, or a grant -- that disambiguates that researcher across name variants, career moves, and multiple scholarly systems, and that is designed to stay resolvable and machine-readable for the researcher's whole career.

ByCASRAI Editorial Board

· Last updated 17 Jul 2026

Worked examples

Is an instance

An ORCID iD (e.g. 0000-0002-1825-0097) entered on a manuscript submission, which then lets the journal, the researcher's institution, and any funder acknowledged in the paper all resolve to the same disambiguated person record.

Is an instance

A Scopus Author ID or Web of Science ResearcherID auto-generated by a bibliographic database to group a researcher's indexed publications under one profile, distinct from the person's ORCID iD but frequently cross-linked to it.

Is an instance

An ISNI record issued for an individual researcher (the ISNI block 0000-0001-5000-0007 through 0000-0003-5000-0001 is specifically reserved for ORCID-issued iDs that also carry a corresponding ISNI).

Looks similar, but isn't

Not an instance

A DOI is not a researcher identifier -- it identifies a work (an article, dataset, or preprint), not the person who created it.

Not an instance

A ROR ID is not a researcher identifier -- the Research Organization Registry identifies institutions and research organizations, not individuals.

Not an instance

A university email address or single-sign-on username is not a researcher identifier in this sense: it typically changes when the person moves institutions, so it cannot follow them across a career the way ORCID, ISNI, or a publisher author ID is designed to.

A researcher identifier is a persistent, unique digital identifier for an individual person working in research — distinguishing that person from every other identifier type in the scholarly-communications ecosystem, which mostly identify things a researcher produces or belongs to (a DOI for a paper, a ROR ID for an institution, a grant number for an award) rather than the researcher as a person. The core problem researcher identifiers solve is name disambiguation: author names are not unique (many researchers share a surname and initials), and a single researcher’s own name may be transliterated, abbreviated, or spelled differently across a career, across publishers, and across countries.

Major researcher identifier systems

No single system has universal adoption, so several coexist and are increasingly cross-referenced:

ORCID iD — the most widely adopted researcher-controlled identifier, a free 16-digit iD that a researcher creates and maintains themselves, and that a growing number of funders, journals, and institutions require or auto-populate at submission. See ORCID iD and ORCID record.
ISNI (International Standard Name Identifier) — an ISO-standardised (ISO 27729) identifier for public identities across creative and research sectors, issued by national libraries and other registration agencies as well as ORCID; see ISNI.
Scopus Author ID and Web of Science ResearcherID — proprietary identifiers auto-generated (Scopus) or self-claimed (Web of Science) by the two major citation databases to group a researcher’s indexed output, useful for citation metrics within that database but not portable outside it the way ORCID is intended to be.
Institutional or national researcher-ID schemes — some countries and university systems maintain their own researcher registries (often themselves cross-walked to ORCID) for local reporting purposes.

How a researcher identifier differs from other identifier types

It is easy to conflate “researcher identifier” with the broader family of persistent identifiers (PIDs) used across research infrastructure. The distinguishing question is always what is being identified:

A DOI identifies a specific work (article, dataset, preprint) — not its author.
A ROR ID identifies a research organization or institution — not an individual affiliated with it.
A grant or award number identifies a funded project — not the researchers named on it.
A researcher identifier identifies the person, and is designed to remain stable as that person changes institutions, publishers, and even legal name.

For how these identifier types are meant to work together rather than in isolation, see Identifier Crosswalk: Connecting DOI, ORCID, ROR, and Institutional IDs in Practice and Persistent Identifier Federation Across Research Infrastructure.

Why researcher identifiers matter

Beyond disambiguation, a stable researcher identifier reduces duplicate manual data entry (ORCID’s auto-population/import features let a journal, funder, or institution pull a verified publication or employment record directly into a system rather than re-keying it), supports accurate authorship and contribution reporting alongside frameworks like CRediT, and increasingly underpins funder and institutional reporting requirements, since a correctly asserted identifier lets a CRIS or grant-management system link one researcher’s outputs, affiliations, and awards without relying on name matching alone.

Frequently asked questions

Is ORCID the same thing as “a researcher identifier”?

ORCID is the most widely adopted example of a researcher identifier, but the two terms are not interchangeable — ISNI, Scopus Author ID, and Web of Science ResearcherID are also researcher identifiers, and a given researcher may legitimately hold several at once.

Do researchers need more than one identifier?

Often yes in practice, even though ORCID is designed to be the single researcher-controlled hub: a researcher may still separately hold a Scopus Author ID or ResearcherID simply because those systems auto-generate one from indexed publication data, regardless of whether the researcher has also registered for ORCID.

How does a researcher identifier relate to a CRIS?

A current research information system (CRIS) typically stores a researcher identifier as a core field on each person record, using it to link that person to their outputs, grants, and affiliations across the institution’s other systems.

References

ORCID, ‘What is ORCID?’ and integration guide documentation (info.orcid.org).
ISO 27729:2012, Information and documentation — International Standard Name Identifier (ISNI).
ISNI International Agency, ‘How ISNI works’ (isni.org).
Research Organization Registry (ror.org) — for the institution-identifier contrast described above.

Use in your systems

JATS XML <role> element

xml

<role vocab="credit"
      vocab-identifier="https://casrai.org/dictionary/"
      vocab-term="Researcher Identifier"
      vocab-term-identifier="https://casrai.org/dictionary/term/researcher-identifier" />

Schema.org DefinedTerm (JSON-LD)

json

{
  "@context": "https://schema.org",
  "@type": "DefinedTerm",
  "@id": "https://casrai.org/dictionary/term/researcher-identifier",
  "name": "Researcher Identifier",
  "identifier": "https://casrai.org/dictionary/term/researcher-identifier",
  "description": "A persistent, unique digital identifier assigned to an individual person -- as distinct from an identifier for a work, an institution, or a grant -- that disambiguates that researcher across name variants, career moves, and multiple scholarly systems, and that is designed to stay resolvable and machine-readable for the researcher's whole career.",
  "inDefinedTermSet": "https://casrai.org/dictionary/domain/persistent-identifiers#set",
  "url": "https://casrai.org/dictionary/term/researcher-identifier",
  "sameAs": [],
  "license": "https://creativecommons.org/licenses/by/4.0/",
  "publisher": {
    "@id": "https://casrai.org/#organization"
  },
  "dateModified": "2026-07-17T21:41:35",
  "inLanguage": "en"
}