A comprehensive resource that allows users to evaluate and compare journals using citation data drawn from scholarly and technical journals from publishers in over 80 countries. It is the only source of citation data on journals, and includes virtually all areas of science, technology, and social sciences.

Essential Science Indicators is a compilation of performance statistics and trends extrapolated from counts of articles published in scholarly journals and the citations to those articles. Article counts and citation data are derived from journals indexed in Web of Science Core Collection (Science Citation Index Expanded and Social Sciences Citation Index only) over a 10-year period.