Enter a DOI (up to 15, separated by commas), a single ISSN, ISBN, ORCID, or PMID to retrieve article metadata, metrics, retraction status, and more. Any other text searches CrossRef. Prefix with worldcat or book to search WorldCat instead. Each result also offers an optional connections view showing a paper's references and the works that cite it.

2025: CrossRef registered 13.2M, where 8.75M are academic (articles, preprints, reports) · DataCite 1M academic · together ~95% of 2025 academic DOIs globally.