Skip to Main Content

Web of Science: Using a Citation Database: Citation Database Coverage

Citation Databases

Scope and Coverage of Web of Science, Scopus, and Google Scholar

What's the Difference?

Are you looking for "everything" published on a topic, or the most important papers?  All three databases have a large overlap in their coverage, and each covers material that the others do not. If you can only search one, consider the differences in their selection criteria. 

  • WoS covers many fewer journal than Scopus, but it selects only "top tier" journals: those most likely to publish major scholarly papers.
  • Scopus covers more journals and more international journals than does WoS. 
  • Google Scholar only includes papers if they have online abstracts or full-text. No one knows how much of the scholarly literature they cover. With Google Scholar, you can't know what you are missing.

Do you need to identify core articles published before the dawn of the Internet? WoS has full citation data for every paper it indexes back to 1900; Scopus has that data back to 1996. We don't know how far Google Scholar goes back.

Do you need accurate citations for your paper's reference list or a bibliography? It's better to use Web of Science or Scopus. Citation errors occur in all databases, but Google Scholar's bibliographic information is extracted by robots performing an automated Web search. As Google points out, this system may lead to incorrect identification of bibliographic information, especially if metadata on publisher Web sites is irregular. You may notice citation errors and/or duplicate citations when you search Google Scholar.

How do you think the information you need will have been published?  Google Scholar covers many more types of documents than WoS and Scopus, e.g., dissertations, books, technical reports and more. Google Scholar is great when you are looking for more than journal articles.

For a concise summary of similarities and differences, please see the table below which compares the coverage of Web of Science, Scopus, and Google Scholar:


Web of Science


Google Scholar

Journal Content 12,000+ journals 21,000+ journals Google Scholar indexes individual papers, not journals. It does not specify how many papers it indexes.
Coverage 1900 to present, coverage varies by title 1996 to present for 60% of content, remaining 40% of content dates back further, as far back as the 1820s in some cases. Not specified.
Specialty Areas Interdisciplinary: Chemistry, medicine, science, social science, arts & humanities Interdisciplinary: science, technology, medicine, social sciences and arts & humanities Not specified.
Comments WoS also includes over 30,000 books, and conference proceedings for a large but unspecified number of conferences. Scopus also includes metadata for over 16,000 books and cross-searches 25.2 million patents from five patent offices (US Patent & Trademark Office, European Patent Office, Japan Patent Office, World Intellectual Property Organization and the UK Intellectual Property Office) The Google Scholar about page indicates it indexes, "journal and conference papers, theses and dissertations, academic books, pre-prints, abstracts, technical reports, court opinions, patents, and other scholarly literature from all broad areas of research." For more info, visit Google Scholar.


Information sources: