UniProt is a comprehensive and freely accessible database of protein strings and functional information, established by EBI, the Swiss Institute of Bioinformatics (SIB), and the Protein Information Resource (PIR).

The most important component of UniProt is UniProtKB, a protein database that comprises two main parts:

UniProt uses a database format similar to that employed by EMBL, although it differs slightly in annotation; a detailed description of UniProtKB/Swiss-Prot format provided here.