Crossref
The DOI backbone of scholarly publishing — metadata that ties the literature together.
At a Glance
- Publisher
- Crossref (a nonprofit membership organisation)
- Coverage
150M+ records of journal articles, books, conference papers, datasets, and preprints with DOIs, references, funding, and license metadata (verify current counts).
- Access
Free; open REST API and metadata dumps.
- Free alternative
- It is free; OpenAlex is built on it.
- Regional
Global; the infrastructure most other tools rely on.
Our Take
Crossref is not a search interface so much as the plumbing beneath scholarly discovery — the DOI registry whose open metadata (references, funders, licenses, ORCIDs) feeds OpenAlex, Unpaywall, reference managers, and much else. For anyone building research tools or doing metadata analysis, the free API is foundational. It is not where you search the literature as a reader; it is where the identifiers and links come from. Use it as your metadata and DOI backbone; use OpenAlex or a citation index for reader-facing discovery.
Power Tips
- Use the Crossref REST API to resolve DOIs, pull references, and fetch funder and license metadata at scale.
- Check Crossref for the canonical DOI and metadata before trusting a scraped record.
- Remember OpenAlex, Unpaywall, and your reference manager are built on this — go upstream when metadata looks wrong.
Alternatives & Complements
OpenAlex, DataCite, Unpaywall, ORCID
Figures last verified: June 15, 2026