KGen is an extension for Firefox web browsers that displays the strongest keywords on a particular web page. Words on the page repeated more than once are ranked by “weight” (a user-tunable algorithm based on html tags and page placement), number of repetitions on the page, and “position” (which appears to be how far down in the page’s code the keyword appears, relative to other keywords in the list). At present, the tool displays only single-word keywords (not multi-word phrases).
To install, in Firefox go to the KGen Add-on Page and download. After installing and restarting Firefox, to use KGen first browse to a page you want to analyze, then select Sidebar > KGen: Keyword generator from Firefox’s “View” menu. The Word List tab shows the keywords with the rankings described above. There is also a Cloud view for a quick graphic representation of the relative strength of the various keywords found. In the Word List view, selected keywords can be copied to your computer’s clipboard to paste and use elsewhere.
While the lack of analysis for phrase keywords limits the tool’s usefulness, particularly for PPC, I found that useful combinations still suggested themselves by glancing from the top ranked keywords to the actual text of the page under analysis. For SEO purposes, right-clicking on any keyword will open a browser tab suggesting common misspellings and lettter-omissions and -substitutions for the word.