NALP Directory of Legal Employers (open access)
NALP has a long history of providing information on legal employers, with a particular emphasis on materials of interest to potential summer associates. Employers can be searched by name or browsed by geographic area, practice, employer size, and/or office size. The search engine can be prickly so run names a few different ways before deciding a law firm of interest is not in the database. Content skews toward larger firms. Resources available on the website include recruitment/summer associate hiring statistics, partnership statistics, and attorney demographics.
Chambers and Partners (open access)
Chambers ranks and provides information on firms and can be searched by region and/or practice. The link above is for US Law Firms; rankings and information for firms outside the US also are available. Chambers Associate provides results from a survey of associates at the top 100 firms, as well as in-depth hiring information, firm profiles, and interview tips.
Am Law 100 (open access for current year)
The American Lawyer compiles financial information on the 100 largest law firms and parses it in various ways, including gross revenue, profits per lawyers, and profitability. The material is updated every April. Prior years' information is available via Lexis Advance (Temple Law access): search for "Am Law 100" in headline and narrow to desired date range.
Vault (open access for rankings; students can use their Temple email address to create an account and access additional information)
Vault has a wide variety of rankings, including Best Law Firms to Work For, Best Regional Law Firms, and the Vault Law 100 (ranked by prestige). Be aware that most rankings are based on associate reviews and so are skewed in that direction.
In addition, multiple other firm rankings are available. For example, American Lawyer has a mid-level associate survey and a ranking of the best firms for advancing women (available via subscription on Lexis Advance Legal News or Law.com; recent print issues in law library closed stacks; ask at the Law Library desk). Above the Law ranks firms on various criteria, such as compensation and firm morale, based on self-reporting from attorneys at the firm. Others are out there too; remember to check the rankings' criteria and information sources before deciding whether to put stock in a particular set of rankings.
Westlaw Litigation Analytics (Temple Law subscription only)
Westlaw's litigation analytics has a law firm search option to view a firm's state and federal litigation statistics, which can be broken down by case type, filing role, and outcome.