No one knows for sure, but the accepted standard for a keyword density is between 3% and 5%, to get recognized by the search engines. 5% is probably a maximum you should not exceed.

Remember, that this rule applies to every page on your site. It also applies to not just one keyword, but also a set of keywords that relates to a different product or service. The keyword density should probably be between 3% and 5%. Then...

• Match keyword tag with content. Ensure that the keyword meta tag has around 900 characters or 25 words.

• Ensure that the keyword density in between 3-10% . And, avoid using the same word more than once in a sentence. Check keyword validators to determine the exact density percentage.

• Try and maximize use in the top half of the page. Many search engine spiders do not go beyond 25-50%.

• Be smart and spell your keywords with variations and also include plurals.

Search engines may not place as much importance on keyword density as they once did, but it is still something you should monitor as select content for your web pages.