The quartile (Q) of a journal can be found by viewing its impact factor and number of citations on the journal's official website or in databases such as Web of Science or Scopus. Some researchers and scholars also compile their own journal rankings, which can help determine the quartile of a journal.

Each subject group of magazines is divided into four quartiles: Q1, Q2, Q3, Q4. Q1 is occupied by the top 25% of journals in the list; Q2 is occupied by journals in the 25 to 50% group; Q3 is occupied by journals in the 50 to 75% group and Q4 is occupied by journals in the 75 to 100% group.

Note: An Impact Factor is only one measure of the relative importance of a journal, individual publication, or researcher to literature and research. Quartile Rank (Q1, Q2, Q3, Q4) – journals that appear in the first quartile of a list (Q1) represent the top 25% of journals in that subject discipline.

The JCR provides quantitative tools for ranking, evaluating, categorizing, and comparing journals. The impact factor is one of these; it is a measure of the frequency with which the “average article” in a journal has been cited in a particular year or period.