Keyword Density, SEO Relevance Factor

Part of: Full Stack SEO Best Practices
Part of: Tenured SEO
Published: 09-25-2024
by Wayne Smith

Keyword density is an evergreen SEO factor in determining the subject content of a text document. A paragraph written using standard grammar rules will have the subject used at least once, but often more than once. Closely related factors of exact match and keywords near each other can easily be part of the same algorithm.

For Google Only Optimization, (GOO), keyword density is not the only way to determine page relevancy. It can be confirmed as, or confirmed not, to be a factor by having two pages; One without keyword density and one using the keyword. A factor would place one page higher than the other. When a related entity is used as an alternative to the keyword (entity density) ... the related word provides relevancy.

Normal ranges for keyword density

The normal ranges for how many times a keyword is used is based on subject and type of content.

• A 0.10 or 10% density would have the keyword once per sentence. Is natural in e-commerse listings with short descriptions.
• A 0.03 or 3% density would have the keyword once in a paragraph of three sentences.
• A 0.01 or 1% density would have the keyword once in ten sentences ... can be normal when other terms fill in for the topic.
• A 0.001 or 0.1% density would use the keyword once in 1000 words.
• A .05% would have the keyword once in a page of 2000 words ... Generally somebody reading it would not consider it relevant with the keyword ... it may also be that % was added to the end of the value when the intent was 5%.

Keyword density is a quantifiable factor-- Determining the frequency of a word in a document is both fast and easy; It works with text documents regardless of size. It is a factor because, like it or not, a document focused on a subject needs to use the word it is explaining.

Non-text documents

There is content other than text documents published. Keyword density was never the only or exclusive relevancy factor for search engines. Never an exclusive factor in SEO for relevancy.

It is not the only factor; Excite almost became the number one search engine because they pioneered the concept that having more than one page about a search term, known as a silo or topical cluster was a better or additional factor -- although keyword density was used at the page level.

Tie Breaker SEO Factors

Regardless of the points of view for which algorithm is the most important ... The sheer volume of websites means there will be ties and additional algorithms keyword density, off-page, or a different on-page algorithm will need to break those ties. SEO for competitive terms needs to use tiebreaker factors. Additional algorithms such as what Excite pioneered or Google's Page Rank - U.S. patent 6,285,999 - January 9, 1998, expired on January 9, 2019, after 20 years.

The Google Link Bomb "who is more evil than satan himself," no longer works today; Both the source content and the destination content need to have relevancy for the keyword, topic, or entity for Page Rank. If one only focuses on, if a link is spam or not, pages that are not relevant are spam pages; Pages that are relevant because they are on topic, (measurable by keyword density, entity density, or other), are not spam.

Nominal Keyword Density in long-tail SEO (semi-deprecated see below)

Adding keywords to a document with a keyword density of 1% can become unwieldy. But, with mixed content having a 5% keyword density for the main keyword the main keyword remains relevant when additional keywords are added.

A 5% + 3% can be used. With a keyword density of 5%, the main keyword would be the most frequently used keyword on the page and with additional keywords at 3%, they would be less frequent than the main keyword ... the page remains relevant to the main keyword but shows up for searches that include the 2nd keyword.

User navigation aids would normally be needed to be used for long-tail SEO. Headlines, table of contents, and images would all increase the keyword density to keep the document on topic.

The long tail keywords should appear within or near each other in some but not all usages on the page ... in HTML they need to be in the same paragraph tag.

Using related entities does not change or remove the keyword density from a normal written document but it is a refinement of relevancy algorithms. Related and long-tail search results are normally improved when a search engine uses entities. Entity-based search engines also improve the relevancy algorithms by using entities as co-factors.

Entity density would not be how often a related entity is used but how many, (relevant) entities are used in the document. The usage in normal English would still have the main keyword used in a paragraph but also have a related entity in the paragraph. Additional paragraphs would have different entities.

Entities as co-factors to keyword density

In the same way, keyword density is a co-factor to page title, and headline tags for relevancy for the keyword. Relevant entities are co-factors or alternative forms of the keyword.

Entity Based Long tail

A related entity can, if used more than once, be a long tail keyword with the main keyword that exists in the same paragraph. The density of the main keyword remains between 1%-3% which is lower than the above "Nominal Keyword Density in the long tail."

Relevant Entity

For the sake of this article: A relevant entity is a common entity used with the main keyword. The closeness of the entity would be how many times these two entities are searched for in the same query.