Recent Improvements to Crossref’s Metadata Search (

We have made some improvements to Crossref’s Metadata Search service ( If you are a regular user of Metadata Search, the main change in behaviour you should notice is an uptick in the speed of the service, as most of the changes we have made are “under the hood”.

If you are not a regular user, this is your chance to learn something new:

Metadata Search is one of the services we have purpose-built for humans rather than machine interfaces. It allows you to search among all the records included in our REST API and is especially useful for broader searches of the literature or for locating a work whose DOI you do not know. Signing in to your ORCID account on Metadata Search also allows you to manually add search results to your ORCID record.

The changes we have deployed today include the following:

  • The backend logic has been rewritten in Python to make it more scalable and easier to maintain.
  • With the exception of the funder search, Metadata Search now uses the query.bibliographic parameter in sending user queries to the REST API, which returns more accurate results faster and more efficiently.
  • Clicking on the DOI for a search result now opens the corresponding landing page in a new browser tab.
  • The “Add to ORCID” Search & Link wizard has been updated to integrate with version 3.0 of the ORCID API. This has also addressed some legacy issues with the mapping of content types and users being unable to add certain works to their ORCID records.

Aside from these improvements, we are now also able to plan out future tweaks and new features, including:

  • Re-introducing search facets or filters (see this thread for more background on why faceted search was disabled in March 2023).
  • Exposing the subtitles of works in the search results.

Stay tuned for updates on these as we continue to improve the Metadata Search service!


We have recently released another update to Crossref Metadata Search - specifically to our ORCID Search & Link wizard, i.e. the “Add to ORCID” functionality on I’d like to highlight the following improvements:

  1. Improved work type mapping: this means that, for example, when claiming a work registered with Crossref as a book-chapter, you will now find it listed as a “Book chapter” in your ORCID record, where previously ORCID would have listed it as a generic “Other”.
    The mapping is now as follows (Crossref REST API work types → ORCID API v3.0 work types):
  • book, monograph, reference-bookbook
  • dissertationdissertation-thesis
  • edited-bookedited-book
  • book-chapterbook-chapter
  • proceedings-articleconference-paper
  • datasetdata-set
  • journal-articlejournal-article
  • reportreport
  • Other work type → other
  1. Information on work containers: when claiming a work to your ORCID record that forms part of a larger “container”, that container will now be included in the entry on the ORCID platform in more cases. For instance, a journal article will be listed as being a part of the journal it was published in, or a reference entry may be part of a book. Note that this is only possible if the container ISSN or ISBN is included in the metadata registered with Crossref (usually by the publisher of the work).
    See below for an example of this in action for a book in a book series:

Happy claiming!