A measure of the usage of keywords in any content. The usage of keywords should not be more or less in any content; this measure is calculated using the keyword density analysis tool. Also called as Keyword Weight.
Keyword Density (calculated as percentage) is a keyword or phrase appearing on a web page compared to the total number of words on the page. With the perspective of search engine optimization keyword density can be used as a factor in determining whether a web page is relevant to a specified keyword or keyword phrase.
Earlier keyword density was an important factor in how a page was ranked. But with the discovery of webmasters the implementation of optimum keyword density became widespread. It became a minor factor in the ranking. But, nowadays the overuse of keywords (also called as keyword stuffing) will cause a web page to be penalized.
(Nkr / Tkn) * 100
Nkr is equal to number of times a specific keyword is repeated.
Tkn is equal to total words in the analyzed text.
(Nkr * Nwp / Tkn) * 100
Nwp is equal to number of words in the phrase
Example: Suppose for a page about search engine optimization where that phrase is used five times and there are three hundred words on the page, the keyword phrase density is (4*3/300)*100 or 5 percent.
Keyword density is important because search engines use this information to categorize a website’s theme. This also determines which terms the site is relevant to. The perfect keyword density would help in achieving higher search enginepositions. Keyword density should be balanced correctly.
In the market there are many tools to analyze Keyword Density bye the name of Keyword Optimizer, Keyword Analyzer, Keyword Position Check, Keyword Typo Generator, Keyword Difficulty Check etc.