For a quick introduction to the topic of Journal Impact Factor, see a tutorial from Ebling Library for the Health Sciences.
Because impact factors vary among disciplines, one cannot meaningfully compare two journals in different disciplines using impact factors. For this reason, it is helpful to see how a journal ranks based on other journals in the subject category. First find the journal to see what discipline or subject category/categories it falls within. Then find the total number of journals in the subject area. Subtract the ranking of the journal from the total number of journals and divide by the number of journals in the subject area minus 1. Thus you will find the percentile ranking.
Formula:
n=number of journals in the subject category
n-rank/n-1 x 100 =percentile
Quantitative analysis of journals is a way traditional peer review may be augmented to gain a more complete picture of a scholar's impact in his chosen field. Three measures can be used:
Knowing the impact or importance of the journal can help in decisions about where an author will choose to submit an article. Libraries and librarians also use journal rankings to make decisions about collection development.
The established source for journal ranking. A database that can be accessed through Web of Science or Web of Knowledge. Journals may be searched by individual title, by date, or by subject category. Learn more about JCR rankings from these tutorials
In addition to Journal Citation Reports, there are some other sources for journal rankings. These include:
A free and searchable database, Eigenfactor covers the natural and
social sciences and "also lists newsprint, PhD theses, popular magazines
and more." Eigenfactor scores rank journals with algorithms using the structure of the entire
citation network (adjusting for citation differences across disciplines)
to evaluate the importance of each journal.
The Eigenfactor is now included in Journal Citation Reports.
It continues to be listed here for use on its own.
The website include several quick top ten lists in science, social science, university theses, newspapers, and magazines.
This source ranks journals that are indexed by ISI's Science Citation Index. The website allows you to customize your ranking and is interactive.
SCImago Journal & Country Rank
A free source that uses data from Elsevier's Scopus database. Includes a "compare" feature that compares journal citation among countries. There is also a "map generator" that shows citation relationships by country.
Australian Research Council Rankings
There is a new way for scholars to look for the highest-ranking journals in their field. The Australian Research Council (ARC), as part of its ongoing evaluation of Australian academia, has ranked 20,712 academic journals worldwide. Each journal is assigned a Field of Research code and a letter grade. The system of letter grades runs from A* to A, B, and C, with A* and A amounting to roughly the top 20 percent of journals in a field, B the next 30 percent, and C the bottom half
A Columbia University panel discussion on the debate about the best way to rank the importance and influence of scholarly publications. Panelists: Marian Hollingsworth, director of Publisher Relations at Thomson Reuters and former assistant director of the National Federation of Abstracting and Information Services; Jevin West, an Achievement Awards for College Scientists Fellow at the University of Washington's Biology Department and head developer for Eigenfactor.org; and Johan Bollen, a staff researcher at Los Alamos National Laboratory and the principal investigator of the MESUR project.