CrossRef

Crossref is a non-profit, open-infrastructure organisation that supports scholarly communication by assigning persistent identifiers (DOIs) and managing open metadata for research objects (articles, books, data, grants) worldwide. 

Who it serves & how
Crossref serves publishers, research institutions, libraries, funders and the wider research community.

• Publishers and content-creators register DOIs for their outputs and submit metadata about them. 
• Researchers and institutions benefit because Crossref makes metadata freely available via APIs, aiding citation linking, content discovery and credibility.
  For example, if you publish a journal article, using Crossref ensures your work has a stable identifier and your metadata becomes part of the global scholarly network.

Key features & value

• DOI registration: Crossref is an official DOI registration agency via the International DOI Foundation. 
• Open metadata: Metadata (authors, titles, funders, publication date, references) is openly accessible for reuse and integration. 
• Services:
  • Cited-by linking (tracks which items cite which) 
  • Event data (mentions in social media, policy, etc.) 
  • Funders registry (links research objects to funding) 
  • CrossMark (document status checking) 
• Scale & reach: Thousands of members and millions of records, billions of DOI resolutions and metadata queries monthly. 

Considerations

• While metadata is open and DOIs provide persistent links, Crossref does not host full-text content of articles—just the metadata and identifiers. 
• Quality of metadata depends on member input, incomplete or inaccurate metadata can reduce utility.
• For authors or small publishers, joining and assigning DOIs involves membership and per‐record fees (or institutional arrangements).