Create, curate, and connect linked data entities to improve metadata visibility

Photo illustration: OCLC Meridian interface and linked data code
Photo illustration: OCLC Meridian interface and linked data code

OCLC Meridian® is an intuitive web application and set of APIs that allows libraries to create, curate, and connect linked data entities. Enrich your metadata by creating connections to existing values in MARC records and other datasets across the global information ecosystem.

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Improve library discoverability and relevance for users

Create WorldCat Entities linked data using Meridian to improve your library’s discovery, findability, and relevance across the web by integrating metadata where users search for information. Because WorldCat Entities data can be accessed in new ways by libraries, partners, and services across the web, important resources and knowledge collections are visible and useful in more online environments.

Photo illustation: WorldCat Entities interface
Photo illustation: Librarian working at her desk

Integrate linked data management into your existing workflows

With Meridian, you don’t need to go “all in” at once. You can contribute in ways that make sense for your library or organization, without disruption to current workflows. Use the web application to create, curate, and connect WorldCat Entities data one at a time, or use the suite of APIs to easily convert and leverage existing metadata at scale.

Discover, emphasize, and analyze important relationships

A suite of WorldCat Entities APIs enables users to connect identifiers from disparate sources (such as ORCID, ISNI, VIAF, etc.), learn of changes to WorldCat Entities data, and retrieve subsets of related data from WorldCat Entities and WorldCat for use in local discovery applications.

Photo illustation: Data from a WorldCat Entities file

Contribute to a scalable, sustainable network of linked data

Create linked data entities that can improve research, analysis, and discovery across diverse types of data.

Connect to any other library or nonlibrary dataset supported by linked data technology.

Integrate with existing MARC records and other datasets, systems, and services.

Icon: WorldCat Entities

150+ million WorldCat Entities

Icon: WorldCat Entities URIs

400+ million WorldCat Entities URIs added to WorldCat MARC records

“Evolving library data into linked data frees the knowledge in library collections and connects it to the knowledge streams that inform our everyday lives—on the web, through smart devices, and using technologies like AI.”

Jeff Mixter
Senior Product Manager, Metadata and Digital Services, OCLC

Photo: Jeff Mixter

Easily convert and leverage your existing metadata at scale with APIs

Developers can take advantage of a suite of WorldCat Entities APIs that provides different levels of programmatic access. APIs are backed by the latest privacy, security, and compliance standards—visit our Trust Center to learn how OCLC keeps your data safe.

Icon: Entity Management API

Entity Management API


Create and curate WorldCat Entities linked data

Icon: Entity Search API

Entity Search API


Search for identifiers that match existing descriptive metadata

Icon: Entity Changes API

Entity Changes API


Learn when there are changes to WorldCat Entities data

Icon: PID Lookup API

PID Lookup API


Connect persistent identifiers (PID) from multiple vocabularies

Icon: Entity Connections API

Entity Connections API


Retrieve subsets of related data for use in local discovery applications

Icon: Entity Query API

Entity Query API


Query the entire WorldCat Entities dataset

Learn about OCLC’s linked data strategy

Illustration: Linked data evolution

Linked data as the next evolution of library metadata

OCLC recognizes metadata and metadata expertise is more important than ever for the sharing of knowledge. Learn about our long-term strategy focusing on expertise, data, infrastructure, and tools.

Learn more

Illustration: Library linked data

An introduction to linked data

OCLC’s Jeff Mixter introduces and defines linked data for libraries, putting it into the context of today’s cataloging environment.

Read the Next blog post

OCLC Next blog: Making an impact online

Making an impact online

The shift toward linked data isn’t just a technology upgrade, but a long-term strategy for enhancing the findability and accessibility of library resources.

Read the Next blog post

Why choose Meridian?
Meridian is a fundamental step forward in making linked data a reality for libraries.

  • Integrate with MARC-based catalogs and other datasets within existing workflows
  • Connect identifiers across disparate vocabularies and authorities like ORCID and VIAF
  • Available globally as a stand-alone service or as an addition to your OCLC cataloging subscription
  • Collaborate with a growing network of metadata professionals in the OCLC Community Center

Join the metadata evolution with Meridian

Start creating WorldCat Entities, descriptions, and connections today, and begin the transition to linked data at your pace. Wherever you are in your linked data journey, we’d like to hear from you.

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Service availability

  • Available everywhere

Support & training resources

Meridian documentation

WorldCat ontology

Upcoming events

Watch this space for upcoming Meridian events

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