SEO keyword density is the number of times that your targeted keyword is found in your web page as a percentage of the total number of words.  It is important to realize that the spiders of search engines index a particular web page based on those words or phrases that have the most number of occurrences.  This is one of the basic ways in which the search engines determine the subject on which your web page is focused on.  Thus, SEO keyword density has always played an important role in the effort to improve the rank of your website in the search engine results pages (SERPs).  Aside from the density, the location of the keywords on the page is also vital.

However, it is also important to avoid keyword overstuffing.  The different search engines vary with regards to their rule on the maximum keyword density that is permitted or they will not include the URL of your web page in the SERPs.  The top ranking search engine Google is the strictest when it comes to the maximum allowed keyword density.  Google only allows a maximum SEO keyword density of two percent while the other search engines can permit as high as five percent.  An important strategy is to comply with the Google maximum of two percent and make sure that the content reads well for site visitors who could be your customers or clients in the future.

It is also important to take into consideration the size of the keyword type and whether the word is italicized or in bold face.  Another factor that could influence the rank of the web page in the SERPs that emerge when someone searches for your targeted keyword is the presence of the keyword in the page title.  It is vital to make sure that you target only one keyword when you are applying the SEO keyword density technique, particularly if this keyword is very competitive. 

It is also essential to make sure that the title for every web page has your targeted keyword.  Another important factor is a site map that links to the various supporting web pages that in turn lead to the primary page.  The anchor text for the links that lead to the main page should contain the targeted keyword.  Lastly, you must have linking partners who are willing to add to their own websites those links that guide their visitors to your main page.