What is importance of keyword density?

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What is importance of keyword density?

The keyword density score for a page is essentially calculated looking at how many times a specific key phrase is repeated in a document, the number of words in that key phrase and the total number of words in the analysed text.

Keyword density is a foundational concept of search engine optimization (SEO). It's important to understand how keyword density works, since it can have a direct impact on your site content's visibility in search engine results pages (SERPs) and on the costs of your online marketing campaigns.

Keyword density has little to do with authority; the quality of your content has some bearing on your domain authority (especially in terms of how many sites link to you), but for the most part, keyword density is about relevance.