This toolbar from Moz lets you see metrics like Domain Authority and Page Authority for every page you visit, analyze links as you browse, expose page elements, and access other SEO tools.
Full Specifications
What's new in version 2.63
General
ReleaseFebruary 3, 2014
Date AddedFebruary 3, 2014
Version2.63
Operating Systems
Operating SystemsWindows 8, Windows 8.1, Windows Vista, Windows, Windows 7, Windows XP