Docs
What the OpenAlex data means, where it comes from, and how to read it.
- About the dataOpenAlex is more than just a catalog of research publications. We do the work of disambiguating and connecting scholarly works, authors, institutions, sources, and other entitie…
- Aboutness"Aboutness" refers to what the stuff in OpenAlex is about. Most of the works in OpenAlex are "about" something, and this aboutness can aggregate up as well to characterize autho…
- API and Data SnapshotWe offer a fast, modern REST API to get OpenAlex data programmatically, with generous free daily rate limits. We also offer periodic snapshots of the full data set. To learn mor…
- Author disambiguationHow OpenAlex identifies and links authors across millions of scholarly works.
- Can I search exact terms?Our text searching defaults to stemming, which means that if you search "research" or "researcher" in the fulltext search field, you'll get the same results because both searche…
- Can I search patents in OpenAlex?We don't currently index patents and so you can't search for them in OpenAlex. We continue to receive feedback from users on features to develop and so far indexing patents has…
- ChangelogRecent updates and changes to the OpenAlex API.
- Data ingest pipelineOpenAlex's data ingest pipeline—including getting works;(https://help.openalex.org/hc/en-us/articles/24347019383191) finding affiliations and citations; and tagging aboutness(ht…
- Do you index DataCite DOIs?We have started work to include DataCite(https://datacite.org/) as a core, trusted repository to mint new works in OpenAlex, but we've run into a number of issues that are preve…
- Does OpenAlex index books?Yes! Books are a foundational form of research output for all types of scholarship, but especially so for the social sciences, humanities, and arts. At the time of writing this,…
- Field Weighted Citation Impact (FWCI)Field-Weighted Citation Impact (FWCI) is a snowball metric(https://arma.ac.uk/wp-content/uploads/2021/08/Snowball-Metrics-Recipe-Book-edition-2.pdf) that takes into account diff…
- French affiliation structures are complex-- how does OpenAlex handle them?We match affiliation text from publications to ROR records. So for instance, when a UMR has a ROR record, we are able to match to the text to that ROR record. Then based on the…
- How accurate is OpenAlex?Our users typically think of accuracy along two axes: content coverage and correctness of metadata.
- How are documents located from repository records?In each OAI-PMH record, we’ll look for a URL that leads to either
- How are repository records matched to published articles?We try to match the articles we find to a published article with a Crossref DOI(https://support.unpaywall.org/a/solutions/articles/44001900286) in one of two ways: by DOI, or by…
- How can I see if OpenAlex has the same papers as other databases?Individually, you can search for paper titles or DOIs in the openalex.org(http://openalex.org/) search bar. For instance, try pasting doi:10.1111/j.1529-8817.2012.01224.x into t…
- How do I make the Unpaywall extension work on my site?The Unpaywall browser extension(https://unpaywall.org/products/extension) gets open access locations by calling our REST API.(https://unpaywall.org/products/api) The API is call…
- How do I read JSONL files?The Simple Query Tool(http://unpaywall.org/products/simple-query-tool) and database snapshot(http://unpaywall.org/products/snapshot) provide results in the JSON Lines text forma…
- How do I use the title search API?The Unpaywall title search endpoint gives you the full DOI API(https://unpaywall.org/products/apiget-doi) response for articles with titles matching your query. 50 results are r…
- How do we decide if a given journal is fully OA?We set the oa\status of an article to “gold” if that article is published in a fully OA journal. We have three steps to decide if a given journal is fully OA.
- How do you assign papers to specific countries?We get information on an author's affiliation from many sources (e.g., Crossref, PDFs, repositories) but always as text, not linked to specific institutions or countries. We use…
- How do you classify works as contributing to the UN SDGs?OpenAlex tags scholarly works with relevant United Nations Sustainable Development Goals(https://sdgs.un.org/goals) (SDGs). These are the 17 global goals adopted by the UN in 20…
- How do you determine work type?Work type is shockingly complex for something that seems so simple. In the upstream data sources that we use (datacite, crossref, hal, etc) there are different taxonomies for wh…
- How does OpenAlex handle predatory and "lower-quality" journals?Unlike legacy indexes, OpenAlex does not try to maintain an arbitrary "quality" bar. We cover all scholarly works.
- How does OpenAlex work?OpenAlex is a map of the world's research ecosystem, linking components (like papers, institutions, journals, topics, SDGs, authors, etc.) to one another.
- How is OpenAlex "open?"Open Science is an international movement to make science (and its benefits) accessible to all of society (scientists, entrepreneurs, non-profits, the public, etc.). For some in…
- How is the best OA location determined?When an article has more than one OA location, we need to decide which is the most current, authoritative version, which is first in oa\locations and is called the best\oa\locat…
- How sustainable is OpenAlex?Ensuring that OpenAlex continues to be completely open and free means putting a lot of care into our sustainability plan, which relies heavily on the Principles of Open Scholarl…
- Institutions and Raw Affiliation String ParsingThis page contains all information related to our institution parsing. This help page will be updated with the latest information as it becomes available.
- Is OpenAlex data used in University rankings?Currently, we know about three different mainstream University Rankings that are using our data:
- KeywordsKeywords in OpenAlex are short phrases that describe what a work is about. There are over 26,000 keywords in the system, and each work can be tagged with up to 5 of them. Keywor…
- Link Resolver IntegrationsUnpaywall is used as a data source in several third-party link resolvers, for example SFX(https://knowledge.exlibrisgroup.com/SFX/KnowledgeArticles/HowtoEnabletheUnpaywall\(form…
- Open Access (OA)There are many ways to define OA(https://peerj.com/articles/4375/literature-review). OpenAlex uses a broad definition: having a URL where you can read the fulltext of this work…
- Paper version definitionsUnpaywall reports three categories of paper version, based on the DRIVER Guidelines v2.0 VERSION(https://wiki.surfnet.nl/display/DRIVERguidelines/DRIVER-VERSION+Mappings) standa…
- Preventing Code Injection - Using Text From Unpaywall SafelySome fields in Unpaywall records include text from external sources like Crossref. If you're simply viewing an Unpaywall API response in a browser or reading a spreadsheet from…
- Recommendation for IRs: License reportingUnpaywall can report the license terms articles in your repository are distributed under. If you know the license, you can include it in the OAI-PMH record in a rights element l…
- Recommendation for IRs: Version reportingUnpaywall reports the version(https://help.openalex.org/hc/en-us/articles/41193818736663-Paper-version-definitions) of the full-text papers it finds.
- Should I use Subfields or Concepts for my search?Concepts(https://docs.openalex.org/api-entities/works/work-objectconcepts) and Subfields (linked to Topics(https://docs.openalex.org/api-entities/topics)) are both different way…
- Sources in OpenAlexWorks are associated with sources, such as journals or repositories. In many cases, a work can have multiple sources. For example, it may have been published in a journal, but a…
- The reference counts in OpenAlex seem off. Why is that?For each Work in OpenAlex, we have a field called referenced\works(https://docs.openalex.org/api-entities/works/work-objectreferencedworks) that is meant to list the works that…
- TopicsOpenAlex organizes scholarly works into roughly 4,500 research topics, arranged in a four-level hierarchy: domains (4), fields (26), subfields (254), and topics (~4,500). Every…
- Unpaywall Change NotesThis page will summarize important changes to our methodology and data sources that we expect to significantly affect the Unpaywall dataset.
- What are CWTS Core sources and how are they different from Web of Science Core Collection?The CWTS Core Source filter(https://openalex.org/works?page=1&filter=primarylocation.source.iscore%3Atrue) in OpenAlex can be used to return only publications from sources that…
- What content does OpenAlex include and how does it compare to other databases?OpenAlex takes inspiration from the Library of Alexandria, wanting to centralize all research information in one place. Likewise, OpenAlex generally covers everything in other d…
- What counts as an Open Access location?We're pretty flexible. In general, if a page makes the full text of an article available for free, either directly on the page, through a PDF link, or in an embedded reader, we'…
- What do the fields in the API response and snapshot records mean?Glad you asked! Documentation for the shared schema is here: https://unpaywall.org/data-format(https://unpaywall.org/data-format)
- What do the host_type values "publisher" and "repository" mean?In general, publisher means this location is provided by the article's original publisher, through the canonical doi.org URL, as a Published or Accepted version. For example, th…
- What does is_paratext mean in the API?Almost anything can have a DOI, so Unpaywall indexes a lot of things besides the journal articles most people use it for. This can be a problem for analyses that use Unpaywall.…
- What does oa_date mean and how is it determined?In each oa\location, the purpose of oa\date is to tell you when the full text of this version of the article was first available at this location. Here’s an example of an articl…
- What is an OA license?There are many definitions of what constitutes an OA license, including the BOAI(https://www.budapestopenaccessinitiative.org/read), OSI(http://osiglobal.org/2018/11/15/osi-brie…
- What is the difference between topics and topic_share in OpenAlex entities?Within some of the OpenAlex entities (institutions, authors, sources), we have separate fields for topics and topic\shares.
- When I look at my repository as a Source in OpenAlex, why is it missing most of our works?We don't currently index works from institutional repositories, but instead if we have record of a work from another source (e.g., Crossref, DataCite, HAL, PubMed, etc), we scan…
- Where do works in OpenAlex come from?Works are scholarly documents like journal articles, conference papers, books and book chapters, datasets, and theses.
- Where do you get APC paid metadata from?We pull APC paid data for publications directly from OpenAPC(https://openapc.net/). But when that information is not available, we estimate it from APC list prices for the journ…
- Where does your citation information come from?When we create a new work record, we source information on the papers referenced by that work from the source of the record (Crossref, PubMed, etc.). When the work is open acces…
- Which DOIs does Unpaywall cover?DOIs can be created by one of several Registration Agencies(https://www.doi.org/registrationagencies.html). The Unpaywall dataset only covers articles issued by one: Crossref(ht…
- Why are some authors assigned to "NULL AUTHOR_ID" (A9999999999)?There are two different scenarios where OpenAlex uses an author ID which falls outside of the normal author ID process. You may come across an OpenAlex Author with these IDs par…
- Why are the counts_by_year numbers different than the count of works in a year?The counts\by\year field is pre-calculated and then stored in entities (like institution, author, source) as a shortcut for users. It gets updated every few months, but it is ou…
- Why does the Unpaywall plugin say this paywalled article is Open Access?In addition to using our API(http://unpaywall.org/products/api), the browser extension looks for a PDF link directly in the page content and, if one is found, displays it as a B…
- Why is affiliation history metadata incomplete?In the author endpoint, we nest a lot of metadata as helpful shortcuts that aren't always complete and up to date. For instance, the citation counts for an author are only recal…