The Keyword Efficiency Index (KEI) or Keyword Effectiveness Index (KEI) is a characteristic value for search engine optimization (SEO), in which the efficiency of the search words is reflected.
The Keyword Efficiency Index is a weighted quotient of the keyword and the search phrase. It is about the ratio between the number of times a keyword is entered into a search engine, (How often is the keyword entered?) and the number of search results. The latter reflects the potential competitors.
The more often a search word is entered and the lower the number of search results, the more favourable the quotient becomes. The lower the KEI index is, the more interesting the keyword is and the higher the chances of appearing high up in the results pages.
Assuming the number of search queries for a keyword is 1,230 and the number of search results 446,612, the KEI index is calculated from the ratio of 446,612 to 1,230. The KEI index is therefore 363.