Compare your keyword density to your competitors.

Keyword density has some general rules such as no keyword stuffing, however its useful to compare your keyword density against your competitors.

Please use this keyword density tool.

http://tools.seobook.com/general/keyword-density/

Keyword density is looked at it all areas of your website, including heading tags, alt tags, webpage titles, anchor links and of course many body text.

If I use multiple versions of a phrase, would it be seen as keyword spam?