The Impact Factor (IF) or Journal Impact Factor (JIF) of an academic journal is a scientometric index calculated by Clarivate that reflects the yearly mean number of citations of articles published in the last two years in a given journal, as indexed by Clarivate's Web of Science.
Please note that the JIF should only be used to compare journals within a discipline, as it is an unstandardized index and does not take into account differences between disciplines such as the average number of citations per article or the frequency of publication. The JIF is calculated once at the end of a given year and is usually published in the middle of the following year with the update of the JCR database.
JCR consists of journals indexed in two databases of the Web of Science Core Collection - Science Citation Index Expanded and Social Sciences Citation Index. To be included in JCR a journal must have been indexed in one of these databases for three consecutive years. The exception to this is if the journal is newly published, in which case one year is sufficient, but the journal will not have its JIF calculated. To find a particular journal, simply go to the database page and use the search engine. In addition to basic information about the journal, the journal profile contains a range of information about the JIF index and the data used to calculate it. Below is the profile of the journal "Metrology and Measurement Systems".
By clicking on the All years tab you can analyse how bibliometric indicators have changed over the years.
