There are a number of tools, both free resources and those that you only have access to via the university network, where you can identify journals by subject and get additional information about them. Below are presented a couple of the most important ones.
Ulrichsweb is a directory of journals and other periodical literature where you can get information on aspects such as:
You can search for individual journals by title or ISSN ("Known Item Search") as well as search for journals by subject, type of journal, language etc. ("Advanced Search"). Furthermore, you can also delimit extensive research results.
DOAJ is a free directory of open access journals. The journals that are listed in DOAJ have undergone a qualitative vetting process based on aspects such as the journals' peer review process, editorial board, contact information etc. See more about this here. Besides this, you can also search for open access articles. DOAJ can answer questions like these:
In the database Journal Citation Reports (JCR) you can find the journals that are indexed in Web of Science and which receives Impact Factors but other similar indicators as well. Included are the journals which are indexed in the sub databases SCI-Expanded (Science Citation Index) and SSCI (Social Sciences Citation Index) of Web of Science. Journals in Web of Science which are categorized within the humanities are not assigned any impact factors although thay are included in A&HCI (Arts & Humanities Citation Index). Among other things you can get answers to questions like:
All the indicators in JCR are based on citations within Web of Science, that is, how many citations, in average, have the journal's articles received during a certain time period. N.B! You can't compare journals based on Impact Factors between different categories!
For a list of all journals indexed in Web of Science, see: Master Journal List
See further under step 3. Analyze the Journals - Impact factors: Web of Science
In the database Scimago Journal & Country Rank you can find journals that are indexed in Scopus and are assigned the indicator SCImago Journal Rank (SJR) but also other types of indicators. Among other things you can get answers to questions like:
See further under step 3. Analyze the Journals - Impact factors: Scopus
In Google Scholar (under the heading 'Metrics') you get top-20 lists of journals within different subject categories. The lists are based on citations to the journals via reference lists in all the publications that are indexed in Google Scholar. This means that the citations may come from other journal articles as well as from reports, student theses etc. and other types of publications.
Google Scholar Metrics (information about the indicators used in the database)
Norwegian Centre for Research Data (NSD) compiles this database of journals and book publishers based on quality criteria. The journals (as well as the publishers) are divided into two quality levels, 1 and 2, where journals on level 2 (approximately 20%) are those that have higher prestige within the research community. The database is multidisciplinary.
ERIH PLUS was created by European researchers and the Standing Committee for the Humanities (SCH) at the European Science Foundation (ESF) and contains journals within the humanities and social sciences. The database is managed by NSD (Norwegian Centre for Research Data) since 2014. In order for a journal to be indexed in ERIH PLUS it has to meet a number of quality criteria.