Thursday, June 27, 2013

Keyword Density, Proximity and Frequency

Keyword Density



Keyword density refers to the ratio (percentage) of keywords contained within the total number of indexable words within a web page.The preferred keyword density ratio varies from search engine to search engine. In general, I recommend using a keyword density ratio in the range of 2-8%

The formula to calculate your keyword density on a web page is a


 (Nkr / Tkn) * 100


  • Nkr = how many times you repeated a specific key-phrase
  • Tkn = total words in the analyzed text



where Nkr is how many times you repeated a specific keyword and Tkn the total words in the analyzed text. This will result in a keyword density value. When calculating keyword density, be sure to ignore html tags and other embedded tags which will not actually appear in the text of the page once it is published. keyword phrase, the formula is a


 (Nkr * Nwp / Tkn) * 100


  • Nkr = how many times you repeated a specific key-phrase
  • Nwp = number of words in your key-phrase
  • Tkn = total words in the analyzed text

                             = (3 x (3 / 500)) x 100
                             = (3 x 0.006) x 100
                             = 0.018 x 100
                             Density = 1.8%

where Nwp is the number of words in the phrase. So, for example, for a page about search engine optimization where that phrase is used four times and there are four hundred words on the page, the keyword phrase density is (3*3/500)*100 or 1.8 per cent.

keyword density for the key-phrase 

Density = ( Nkr / ( Tkn -( Nkr * ( Nwp-1 ) ) ) ) * 100. where Nwp = the number of terms in the keyphrase.This general formula allows that the total word count will be unaffected if the key(phrase) is indeed a single term, so it acts as the original formula.

Density = ( Nkr / ( Tkn -( Nkr * ( Nwp-1 ) ) ) ) * 100
              = (9 / (500 – (9 x (3 – 1)))) x 100
              = (9 / (500 – (9 x 2))) x 100
              = (9 / (500 – 18)) x 100
              = (9 / 482) x 100
              = 0.0186721991701245 x 100
              = 1.87%


Keyword Proximity



It measures the distance between two keywords in the text. Keyword proximity is used by some search engines to measure relevancy of a given page to the search request. The idea is that the closer two keywords to each other are, the more relevant the page. So proximity looks at the location of the keyword in the sentence and how often it's being used in that sentence and also takes into account the distance between them. Keyword Proximity is difficult to calculate when two or more keywords are used as keyword combination.  Especially when the keywords are not close together.

Keyword Frequency


Keyword frequency is the number of times a keyword or keyword phrase appears on a single Web page. That you ensure that the most important keyword or keyword phrase is the most frequently use keywords in a web page. But be careful not to abuse the system by repeating the same keyword or keyword phrases over and over again.