National Center for Biotechnology Information (NCBI)
The National Center for Biotechnology Information (NCBI) provides a suite of free, publicly accessible REST APIs for querying and retrieving biological and biomedical data.
The Entrez Programming Utilities (E-utilities) are the public API to the NCBI Entrez system, providing access to over 38 Entrez databases including PubMed, GenBank, Gene, Taxonomy, and Protein.
The BLAST (Basic Local Alignment Search Tool) URL API allows developers to submit nucleotide and protein sequence homology searches via HTTPS.
The NCBI Datasets v2 REST API provides programmatic access to genomic sequences, gene records, taxonomy data, virus sequences, and ortholog information.
The PubChem Power User Gateway (PUG) REST API provides programmatic access to PubChem's chemical compound, substance, and bioassay data.
The PubMed Central Open Access API retrieves citation data, licensing details, and FTP download locations for Open Access articles in the PMC archive.
The PMC ID Converter API translates between PubMed Central identifiers (PMCID), PubMed identifiers (PMID), Manuscript IDs, and Digital Object Identifiers (DOI).
The PMC OAI-PMH service allows bulk harvesting of metadata for all items in the PMC archive and full-text content for articles with Creative Commons licenses.