Some journals are read and cited more than others. Measuring the impact of a journal may help authors identify where to publish. Note that journal impact measures vary across disciplines and cannot be directly compared.

On this page:

Journal Impact Factor

A journal’s Impact Factor averages the number of recent citations to the journal by the number of articles it recently published. Journal Impact Factor considers only a brief period of time and can change from year to year. Impact Factor is based on Web of Knowledge data and can be viewed in either of ISI’s two data sources:

  • Web of Knowledge: Search by journal title. In an article record, click Journal Citation Reports towards the bottom of the record, under "Journal Information."
  • Journal Citation Reports: Compare journals in a subject discipline: view a journal’s Impact Factor with others in its discipline.

SCImago Journal Rank (SJR)

The SJR is a free website based on the citation data tracked in Elsevier’s Scopus database. The ranking system works like the Google PageRank algorithm as it incorporates citation data as well as relationships among journals (via citations).

Eigenfactor Score

A journal’s Eigenfactor Score counts the citations made to a journal over time, but gives more weight to the citations from highly ranked journals than lower ranked ones. Eigenfactor ranks the overall impact of a journal, and not the impact of articles within that journal.


A journal's CiteScore is the total number of citations in a year to articles published in the three previous years, divided by the total number of articles published in those three years. CiteScore is limited to only scholarly articles, conference papers and review articles and does not consider citations from trade publications, newspapers, or books. CiteScore is similar to the Impact Factor but uses Scopus rather than Web of Science to gather its data and three years rather than two as the publication period.

Journal h-index

SCImago Journal Rank calculates a journal’s h-index, or the number of articles in a journal (h) that have received at least h citations.


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