What it is:
The Journal Impact Factor is a calculation of the average citation frequency for a journal over a given period of time. It is a ratio of citations to published items. An Impact Factor is calculated by dividing the number of citations received in a given year by the number of citable items published in the preceding two years.
What it is used for:
The Journal Impact Factor is used to estimate the quality of a journal. A high Impact Factor within a given field is a positive indicator of quality. The Journal Impact Factor was initially developed to help librarians make collection management decisions. It has since become the most common metric to indicate journal quality.
Although the Impact Factor is well-known and commonly invoked, there are some characteristics that you should be note before proceeding:
How to find it:
Journal Citation Report (available through the Libraries)
Cabell's Directory of Publishing Opportunities (available through the Libraries) are descriptive and evaluative metrics for 11,000 social science journals intended to help authors identify publication venues. Some of their metrics include subject area, acceptance rate, and aggregate Altmetric scores.
The Eigenfactor is a measure of a journal's influence similar to the Impact Factor, but weighted for the influence of the citing journal. Eigenfactor was developed in 2008 and is now included as a metric of influence in the Journal Citation Report (available through the Libraries).
Google Scholar H5 Index:
The H5 Index is used by Google Scholar Metrics (freely available) to show the h-index of a journal for items published in the last 5 years. Google Scholar will show the top 100 journals overall and top 20 journals in selected high-level categories.
Journal Citation Indicator:
As a complement to their Journal Impact Factor, Clarivate Analytics introduced the Journal Citation Indicator in the 2021 Journal Citation Report (available through the Libraries). The Journal Citation Indicator is a field normalized journal-level impact metric that can be used to compare journals across disciplines.
Scielo is a bibliographic database of Latin American, Spanish, and Portuguese open access scholarship. Scielo Analytics (freely available in Beta) provide metrics for all journals in their collections. Metrics include access data, publication data, and citation data such as citable items, Google h5 metrics, and citation counts received from within the Scielo network. (Note that their Analytics platform is in development so some content may not have complete metrics.)
Scimago Journal Rankings (SJR):
The Scimago Journal Ranking (freely available) is a metric similar to the Impact Factor. It is built upon the Scopus database and calculates a three year citation window, weighing citations according the prestige of the citing journal. The higher the SJR, the more prestigious the journal.
Source Normalized Impact per Paper (SNIP):
The Source Normalized Impact per Paper (freely available) is a refinement of the Impact Factor from the Center for Science and Technology Studies at Leiden University and built upon the Scopus database that accommodates for differences in citation practices between fields. This metric allows for cross-field comparison of journals.