WorldCat Discovery resources


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Learn about OCLC's support for the NISO Open Discovery Initiative.


See what's included in the central index 

Get the most from the service

WorldCat Discovery video tutorials
Searching in WorldCat Discovery

Watch video tutorials on WorldCat Discovery search and interface features, as well as service configurations for content, staff, and patron-facing features.

Learn how to use advanced search strategies and filter results to optimize your search results in WorldCat Discovery.

Visit the WorldCat Discovery support page for additional documentation, instructor-led courses, and tutorials.

Integrate key WorldCat Discovery features into applications at your library

APIs in the WorldCat Discovery Premium API package leverage popular WorldCat Discovery features to customize, enrich, and extend your discovery services. They have been intentionally designed to maximize accessibility and can be used out-of-the-box. They use OAuth 2.0 for optimal testing and security, and all functionality and naming align with the WorldCat Discovery user interface.

The WorldCat Discovery Premium API package includes:

  • WorldCat Discovery API—Surface WorldCat and WorldCat Discovery central index data in searches, with search functionality such as filtering, browsing, and facets.
  • New Titles API—Display recent acquisitions cataloged in WorldCat on library websites and other places online.
  • Citation API—Automate citation creation in applications via use of OCLC and ISBN values.
  • Suggestions API—Automatically suggest alternate and preferred vocabulary and search terms in end user searches.
  • Access Options API—Embed options for obtaining needed items, like e-resources and open access materials, in search results.
  • Library Profiles API—Surface library profile information to help end users obtain resources they discover through searches.
  • Lists API (coming soon)—Create/delete, manage, view, use, and share lists of library materials to support use cases like class reading lists.

Current WMS and WorldCat Discovery Premium subscribers can login with their WorldShare credentials to obtain a new WSKey. 

Frequently asked questions

General information about WorldCat Discovery

Why does OCLC provide access to both FirstSearch and WorldCat Discovery?

OCLC maintains both FirstSearch and WorldCat Discovery because we understand libraries need to deliver search experiences that meet different user needs:

  • Power searching for library staff and expert searchers
  • Single-search-box discovery of electronic, digital and physical library collections for a broader user community.
Access to both services is included in a FirstSearch/WorldCat Discovery subscription.

How do current WorldCat Discovery subscribers who do not maintain holdings in WorldCat benefit from WorldCat Discovery?

WorldCat Discovery subscribers receive the following benefits from WorldCat Discovery, regardless of the presence of their collections in WorldCat:

  • A new user interface that adapts automatically to mobile devices
  • Access to a central index that represents 3,156 collections of articles, e-books and other e-content
  • Links to full text via an existing OpenURL resolver and from URLs included in the 856 field of WorldCat records.

What additional WorldCat Discovery benefits do WorldCat Discovery subscribers receive when they also subscribe to OCLC cataloging?

Libraries whose collections are maintained in WorldCat and the WorldCat knowledge base maximize the benefits they receive from WorldCat Discovery. In addition to the features listed above, they also receive

  • display of local library resources first in search results,
  • direct links to full-text resources in their e-content subscriptions,
  • a built-in A-to-Z list, and
  • visibility of their libraries' resources in OCLC partner websites where many people begin their research.

Is there an API available for WorldCat Discovery?

The WorldCat Discovery API is currently available as a beta for a limited number of libraries using WorldCat Discovery. While the WorldCat Discovery API is not yet generally available for use by commercial partners, libraries who wish to use the beta version of WorldCat Discovery API are encouraged to visit the OCLC Developer Network and request a key.

What usage statistics are provided to WorldCat Discovery subscribers?

Subscribers to WorldCat Discovery have access to the same type of usage statistics available for FirstSearch. In addition, WorldCat Discovery Services works with Google Analytics, a free tool, to deliver traffic and access statistics for your library.

What does WorldCat Discovery mean for OCLC ILL subscribers?

Authorized ILL staff can use the staff view of WorldCat Discovery for full-featured searching with facets and access to the central index, and then use the "Staff ILL Request" button to integrate discovery results into ILL workflows. Users of libraries that offer patron-initiated requesting search WorldCat Discovery to identify the materials they request through interlibrary loan. ILL staff can also search WorldCat within WorldShare Interlibrary Loan, but all future searching enhancements will occur in WorldCat Discovery; there are no plans to further enhance searching within WorldShare ILL.

Managing a WorldCat Discovery account

I set up new OCLC Services accounts for my staff's use of WorldShare Interlibrary Loan. Will we use the same accounts to access WorldCat Discovery?

Yes. Staff who manage both WorldShare ILL and WorldCat Discovery for your library can do so from the same OCLC Services account. Your ILL staff may contact orders@oclc.org to request access to WorldCat Discovery from your library's OCLC services accounts for WorldShare ILL.

Can library staff customize their library's WorldCat Discovery URL?

Yes. Your library staff can request a change to your library-specific URL by submitting a request to orders@oclc.org.

Using WorldCat Discovery

What advanced search capabilities are provided for expert searchers, such as faculty members or genealogists?

All WorldCat Discovery users may use multiple search options.  Keyword and advanced searching continue in WorldCat Discovery. The advanced search screen displays the most-used searchable fields. 

Experienced searchers may continue to search terms within specific fields using 2-letter field abbreviations, restrict searches to individual databases and view library holdings information within the service. Standard features such as use of Boolean operators, nesting search terms, etc. are also supported in WorldCat Discovery.  

The FirstSearch service also provides the precise, full-featured searching often required by experienced searchers.  

Can library staff view MARC records in the new service?

Yes. Display of MARC records is available for staff of libraries that maintain up-to-date in WorldCat through an OCLC cataloging subscription. Staff must log in to use staff-specific features such as the MARC record display.  

For libraries that use WMS or WorldCat Discovery Premium, with which ILSs does WorldCat Discovery interoperate to deliver real-time availability status?

ILSs that currently interoperate with WorldCat Discovery to provide real-time availability are:

  • ExLibris: Alma, Aleph, Voyager
  • Innovative Interfaces: Millennium, Sierra
  • OCLC: WorldShare Management Services, LBS, OLIB
  • SirsiDynix: Symphony, Unicorn, Horizon
  • TIND
  • Z39.50-only interoperability: Koha

WorldCat Discovery content

What is in the WorldCat Discovery central index?

The central index is an index of metadata for a wide range of databases, articles, e-books, and digital materials libraries provide to their users, including materials from well-known content providers and open access resources. The central index:

  • Represents 3,156 e-resource content collections from OCLC content partners such as EBSCO*, ProQuest, Gale, Springer and many others.
  • Includes databases of the former FirstSearch Base Package (Electronic Books, ArchiveGrid, ArticleFirst, CAMIO Catalog of Art Museum Images Online, OCLC FirstSearch Electronic Collections Online Abstract & Index, OAIster, PapersFirst, ProceedingsFirst, WorldCat Dissertations and Theses, ERIC, GPO Monthly Catalog and MEDLINE). These databases can be selected and searched individually.

4,920,198,403 records are currently searchable through WorldCat Discovery.

As you view the list of collections included in the central index at http://oc.lc/indexDiscovery, note that the collections noted as "Complete" are those for which OCLC and the content provider have negotiated an agreement to surface this metadata through WorldCat Discovery.  Collections noted as "Majority" are those for which WorldCat Discovery Services contains some  metadata for 75 percent or more of the ISSNs or ISBNs indexed in the database or collection  from another source.

What is the difference between the electronic content represented in WorldCat and the electronic content represented in the central index?

Metadata for electronic resources such as websites, e-journals and e-books has been added to WorldCat for many years. Some of the metadata has been contributed by OCLC member libraries and some has been added through OCLC partnerships with leading publishers and content aggregators.

The central index in WorldCat Discovery includes metadata from e-content collections often provided by libraries.  

What is the difference between the central index for WorldCat Discovery and the WorldCat knowledge base?

The central index for WorldCat Discovery and the WorldCat knowledge base are complementary tools that enable information seekers to find and connect to information resources provided by libraries.

The WorldCat knowledge base contains detailed information about library holdings that enables linking from citations to full text in resources to which a library subscribes.

The central index in WorldCat Discovery is a rich index of metadata that provides unified access to a broad range of content, including the following resources:

  • The WorldCat database of 559 million bibliographic records, representing the collections of thousands of libraries worldwide
  • FirstSearch Base Package subscription databases (except Clase and Periodica)
  • More than 200 million article-level records from sources that include HathiTrust, ArticleFirst, MEDLINE, ERIC, British Library Inside Serials, JSTOR, OAIster, Elsevier metadata and others
  • E-resource collections from OCLC content partners such as ProQuest, Gale and others.

Metadata in the central index enables discovery, and library holdings data in the knowledge base facilitates links from citations to full text.

Does my library need to subscribe to collections represented in the central index in order to take advantage of search access through WorldCat Discovery?

The central index for WorldCat Discovery serves as a finding tool for millions of content items.

  • Metadata for some of this content is searchable without a subscription.
  • Some content collections are searchable without a subscription but require a subscription for access to full text.
  • Other content collections require a subscription to search as well as display full text; when your library also subscribes to these content collections, you can use the built-in link resolution functionality provided by the WorldCat knowledge base or another knowledge base already in use at your library to connect users to full text.

An Excel file list of content collections in the central index is available, as well as PDFs for Complete Collections List, Open Access Collections List, Full-Text Searchable Collections List, Remote Database List, and Collections that Require Authentication to Search List.

Does WorldCat Discovery favor specific content sources in search results?

No.  WorldCat Discovery is a content-neutral service. The WorldCat Discovery central index represents collections from a broad range of authoritative content providers, and search algorithms do not favor specific content collections.

What is the relationship between searches of the central index for WorldCat Discovery and searching remote databases not represented in the central index?

The central index is available for searching by users of all FirstSearch/WorldCat Discovery subscribers. Searches retrieve results from WorldCat and the central index. The e-content that a library makes available to its users depends on its subscriptions to e-content collections.

Remote database searching lets libraries also include searches of metadata not included in the central index for WorldCat Discovery as part of users' search experience. Recommended remote databases from EBSCO and ProQuest that are not included in the WorldCat Discovery central index display at the top of search results with an indication of the approximate number of results expected from each. Users can click on a recommended database to connect to the database's native interface to continue searching.   

How do libraries begin to use the WorldCat knowledge base?

Use of the WorldCat knowledge base is included in an OCLC Cataloging and Metadata Subscription. To use the WorldCat knowledge base, complete a knowledge base request form, add data about electronic collections to the knowledge base and activate the functionality. Methods for adding a library's local data to the WorldCat knowledge base are described in Building your WorldCat knowledge base: Choose a method to add your collections (PDF).

WorldCat Discovery subscriptions

Why do libraries need a FirstSearch/WorldCat Discovery subscription for their holdings to display in WorldCat.org and OCLC partner websites?

An OCLC Cataloging subscription supports the cost of maintaining your library's holdings in the WorldCat database. A FirstSearch/WorldCat Discovery subscription covers the cost of making that data accessible to information seekers and machines that integrate information resources through interfaces and APIs.  

A FirstSearch/WorldCat Discovery subscription gives the public access to a library's collections maintained in WorldCat through WorldCat Discovery, WorldCat.org and websites of OCLC partners, such as Google Books, Goodreads, Wikipedia, etc. Through partner websites, searchers will discover libraries' resources in places where they often begin their research and then connect back to libraries from those sites. A FirstSearch/WorldCat Discovery subscription makes discovery of library materials possible through multiple Web destinations with no additional work for library staff.

Does an EMEA WorldCat.org subscription support a library's use of WorldCat Discovery?

EMEA libraries that subscribe to WorldCat.org at Level 3 (which includes access to FirstSearch) may use WorldCat Discovery as part of their current subscriptions. Use of WorldCat Discovery is not included in an EMEA Level 1 or Level 2 WorldCat.org subscription. Libraries subscribing at these levels will continue to expand visibility of their collections through OCLC's partnerships with a growing number of search engines and other popular websites.

Getting started with WorldCat Discovery

What kind of training is available for library staff?

OCLC provides self-paced, live and virtual training for library staff when the service is released. Details about training resources will be provided on the OCLC Support and Training website.

Does my library need to use specific browsers to access WorldCat Discovery?

WorldCat Discovery requires use of the latest version of the following browsers:

  • Mozilla Firefox®
  • Google Chrome
  • Apple Safari
  • Microsoft® Internet Explorer version 11

Newer browser versions are needed to enable use of the new and expanded features of WorldCat Discovery.

If you are not sure which browser is in use at your library, you may wish to consult http://www.thismachine.info/.

Promote WorldCat Discovery in your library



Five different versions of 8.5" x 11" posters that you can print or customize with your library's name and unique WorldCat Discovery URL. Hang all around your campus, community, school or organization.

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Everyone needs a bookmark. Print and then cut the bookmarks apart along the dotted lines.

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WorldCat Discovery helps people easily find and get resources available at your library and in libraries worldwide through a single search of WorldCat and familiar, authoritative e-content collections. It also connects users to your collections via popular websites where people typically start their research.

Service availability

  • Available everywhere (features differ by locale)

Learn more

WorldCat Discovery brochure

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Download the brochure (US Letter)
Download the brochure (A4)

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