What is CiteScore and how is it calculated?
CiteScore is Elsevier's journal metric, calculated from Scopus data. It divides the citations received over four years by the documents published in those same four years. CiteScore 2024, for example, counts citations received in 2021–2024 to documents published in 2021–2024 and divides them by the number of those documents.
Detail
What goes into the calculation
Five document types, in both the numerator and the denominator: articles, reviews, conference papers, book chapters and data papers. Articles in press are not included.
Since when
The four-year window was introduced with CiteScore 2019, released in June 2020. Before that the calculation was different, so earlier values are not directly comparable.
Free and verifiable
The underlying data and the methodology are available for verification without a Scopus subscription, and anyone can recalculate a journal's CiteScore. A new title usually gets its first CiteScore the year after it enters Scopus.
CiteScore is not the Impact Factor
They are metrics from different companies, with different windows and different databases. See the difference between CiteScore and Impact Factor.