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WorldCat is the world’s most comprehensive database of information about library collections. OCLC delivers quality, discoverability and value. Member libraries provide the foundation. Partners support WorldCat growth.
WorldCat is filled with millions of popular and unique items.
Inside WorldCat
OCLC delivers quality
Libraries provide the foundation
Partners support growth
Linked data
WorldCat is the manifestation of the creativity and innovation of the staff of OCLC and thousands of librarians. Unique in scale and unparalleled in data quality, WorldCat makes library collections findable and accessible around the world.
OCLC’s team of expert catalogers and data quality specialists constantly enrich WorldCat records with new and corrected information to ensure that WorldCat contains the highest quality records possible. Library staff members also enhance records through the OCLC Cataloging and Metadata Subscription (previously the OCLC Cataloging Subscription), making these records the industry standard for quality.
WorldCat helps you share what makes your library great to make all libraries better.
By enabling libraries to share high-quality library metadata and bibliographic records with each other, WorldCat has helped librarians dramatically reduce the time they spend on original cataloging. In calendar year 2020, OCLC member librarians copy cataloged 95% of their items from WorldCat, saving an average of 10 minutes per title. These librarians copy cataloged 17,101,022 titles during that year, so they saved around 3 million hours of time, collectively.
Partner content providers add records to WorldCat—sometimes before a resource is published—so library users can find the information they need as soon as it’s available.
WorldCat supercharges library collections
The resources in your library power “light bulb moments” for learners and researchers every day. WorldCat supercharges your collection by aggregating and enriching your library metadata in its cloud-based infrastructure to power greater collection reach and usage.
I’m ready to harness the power of my collection
Make your collections visible.
Data about library collections, which house some of the most authoritative and unique resources in the world, is difficult to share directly from independent library catalogs. The collaborative nature of WorldCat helps libraries take advantage of linked data opportunities to lessen their workloads and to increase their online presence and discoverability. OCLC continues to explore linked data benefits for discovery, authority control, disambiguation and more as part of our work on numerous standards committees and community projects. OCLC also provides data services and downloadable data sets that help programmers and linked data practitioners create and improve their own applications with WorldCat data.
“Work with libraries...”
“As a major data hub, OCLC is well placed to develop linked data services for the library community, and they have made many far-sighted moves over a long period. What I welcome most of all is their willingness to work with libraries to understand how they can help us meet our goals.”
Chiat Naun Chew
Director, Cataloging and Metadata Services
Cornell University Libraries
Ithaca, New York, United States
Read the white paper
“Promise of linked data...”
“You only have to store and index locally the fields that people want to search right then and there. The promise of the linked data universe is that we could go out and get all of that other stuff from somewhere else, live time, on the fly.”
Carl Stahmer
Director of Digital Scholarship
University of California, Davis
Davis, California, United States
Learn about the book
WorldCat brings together valuable information about collection items, electronic resources and the libraries that make them available.
Provide access to knowledge.
If a library’s materials can’t be found, they can’t be used. WorldCat gives people the ability to view library collections from anywhere in the world, giving them access to a rich assortment of information much deeper than what can be found through a basic internet search. WorldCat plays a vital role in getting library resources in front of people both inside and beyond the library on the popular websites where they begin their searches. Librarians can connect library users to library resources by adding WorldCat records into their existing catalogs or through FirstSearch, WorldCat Discovery and WorldCat.org.
“Natural search processes...”
“With WorldCat, library collections are globally integrated into the fabric of the web. Through natural search processes and the social networks people love, users find their way back to their local library.”
Jason Openo
Former Director of Planning & Program Development
The Alberta Library
Edmonton, Alberta, Canada
See our partners
“More visibility...”
“In the old days, people had to consult dozens of reference works—and still they would have incomplete information. The need for a one-stop shop for discovery grew incrementally. A need, a wish, which became a requirement… Because the more libraries, the more content, the more visibility. And that is what we want.”
Geert-Jan Koot
Head of the Rijksmuseum Research Library
Amsterdam, North Holland, Netherlands
Read Rijksmuseum’s story
Share your collections.
WorldCat provides the high-quality data that power discovery of library resources and make library collections visible to the largest resource-sharing community in the world. Since WorldCat is the foundation of WorldShare Interlibrary Loan, libraries can easily see the resources available from other libraries, borrow directly from them and share their resources to meet users' needs. WorldCat also allows borrowing libraries to link users directly to articles provided by lending libraries, giving users the instant access they expect.
“See the content we have...”
“Patrons at other libraries can see the content we have [in WorldCat], and those libraries are requesting to borrow that content from us. Because we're a growing campus, we have been a net borrower for many years. Now we're a net lender—everyone out in the world can see our electronic content, and that's been a really great change”
David Bryden
High Point University Library
High Point, North Carolina, United States
“Visible to many...”
“WorldShare Interlibrary Loan brings together the collection inventories of a lot of libraries [through WorldCat], thereby making them visible to many, including the unique stocks of the Bavarian State Library.”
Berthold Gillitzer
Assistant Head of User Services Department and Head of Document Delivery and Interlibrary Lending Unit
Bavarian State Library
Munich, Bavaria, Germany
Read the Bavarian State Library’s story
Prove your value.
Librarians increasingly rely on data to make decisions about the library’s collections and services and to justify those decisions to library stakeholders and funding organizations. Through WorldShare Collection Evaluation, WorldCat helps librarians compare their collections and gather the data they need to analyze their collection development choices. Librarians can compare their analysis to their own usage and circulation statistics through WorldShare Report Designer to make decisions about the library’s priorities. In addition, GreenGlass uses the data in WorldCat to help libraries manage shared print collections.
“Support student learning…”
“Certainly, our shelves have more materials than we would like them to have, which makes it difficult to expand... . [This SCS deselection project] gives us a better opportunity to have space where we can collaborate together to support student learning.”
Pam Rees
Library Director
Grand View University
Des Moines, Iowa, United States
Read Grand View’s group story
“Collection-level analysis...”
“It’s only by making sure that our records are up to date and synchronized fully with WorldCat that we have the ability to do a collection-level analysis across the community, which will enable us to make decisions … [to] get best value from our collective operations as a research library community.”
John MacColl
University Librarian, University of St. Andrews
Chair, Research Libraries UK
St. Andrews, Fife, Scotland
See how RLUK uses WorldCat
A bibliographic catalog
Everything that’s available through the library, including books, videos, photos and unique objects
A knowledge base
Connection to the library’s e-resources with options for automatic record updates
A registry of library profiles
Information about the library itself, including location, hours and services provided
Learn more about the information inside WorldCat
“Don’t have to micro-manage...”
“The biggest benefit for me has been the time savings. I don’t have to micro-manage my electronic collections and holdings; I used to literally add titles one by one, in some cases. If I know this is happening automatically, I don’t have to worry about it.”
Sandy Cahillane
Electronic Resources and Reference/Instruction Librarian
Bay Path University
Longmeadow, Massachusetts, United States
Learn about the WorldCat community
Growing every day
WorldCat consists of a bibliographic catalog, e-resource holdings and library location information.
Discover what's in WorldCat
Getting better together
OCLC and libraries worldwide collaborate to ensure WorldCat records are the highest quality possible.
Learn about WorldCat quality
Planning for the future
WorldCat puts library resources in front of researchers and keeps up with changing research habits.
See why data strategy is key
Download the WorldCat brochure

Download the brochure (US Letter)

Download the brochure (A4)
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