What it does
Crossref’s REST API exposes publication metadata deposited by its member organisations and supplemented by trusted sources. The JSON service can search and filter works, return a single DOI record, and query related registries such as journals, funders, members, and licenses. Its documented routes return metadata records rather than promising article PDFs or full-text retrieval, so its usefulness depends on what is represented in deposited records and the rights attached to individual fields such as abstracts.
For a bibliography tool or reference-enrichment step, start with a DOI when you have one: the documented /works/doi/{doi} route returns the matching record. When you have only a title or need a batch of candidates, query /works and use its filters, facets, or sampling options to narrow the results. The REST API returns JSON and also has endpoints for journals, members, funders, prefixes, work types, and licenses. These routes make it useful for filling citation metadata or building scholarly search, not retrieving article PDFs.
A practical lookup path
An illustrative first request is GET https://api.crossref.org/works/doi/10.1128/mbio.01735-25. For a small result set, the documentation also shows /works?rows=10. Crossref recommends identifying frequent-use requests with a mailto parameter to use its polite pool. No sign-up is required for the REST API.
Crossref’s metadata comes from member deposits and trusted sources. A missing date, abstract, or other field may reflect what was deposited rather than a failed search, so treat returned values as bibliographic evidence to verify for high-stakes cataloguing. The documentation notes that most metadata is not subject to copyright, but some abstracts may be copyrighted; do not assume every returned field has the same reuse status. Pricing for API access was not stated in the documentation reviewed.
Strengths
- One API covers works, DOI records, journals, member organisations, funders, licenses, and other metadata types.
- Search results can be filtered, faceted, sampled, and returned as JSON without requiring an account.
- The DOI route provides a direct way to enrich a citation when a persistent identifier is already known.
Watch out for
- The API exposes deposited metadata, so completeness and corrections depend in part on member records and trusted-source contributions.
- Some abstracts in results may be copyrighted even though most metadata is not subject to copyright.
Best for
- Adding DOI-based publication details to reference managers, catalogues, or research tools
- Searching scholarly metadata across works, journals, funders, and member records
Sources
- REST API - Crossref (Oct 26, 2026)