Keyword Density – What is Keyword Density or KWD?

Keyword density is the ratio of keywords or key phrases to the total number of words on a given page.

Keyword Density in SEO

SEO in the early stages of this art thought that search engine algorithms paid close attention to keyword density when indexing and ranking a page. The number of appearances of the same keyword in a document divided by the total number of words will result in the value, called Keyword Density.

The ideal keyword density was believed to be between 1-2% so that the content is optimized to rank higher on search engine results pages (SERPs) without sounding unnatural or repetitive. For keywords with more competition SEOs would even implement a density of 3-4%.

Indeed, there seemed to be correlations between higher keyword density and better rankings.

Too much keyword stuffing could lead to search engine penalties. From today’s perspective on SEO, this is probably less because of the “too high” keyword density itself but rather to unnatural language, which search engines rather want to avoid to rank well.

Alternative ideas to KWD in SEO

Word stem density

Word stem density is an alternative to keyword density that SEOs use to optimize a website’s content. It is a metric used to measure the number of keywords or key phrases that are variations of the same word.

For instance, if a keyword is ‘marketing’ then its variations would be ‘market’, ‘marketer’, etc. This way, the word stem density provides a more comprehensive metric that includes not just one word but also its variations. Word stem density can be quite useful in optimizing content as it is believed to increase the likelihood of a page appearing higher on SERPs.

Furthermore, it also reduces the risk of keyword stuffing and provides more relevant content for readers.

Latent Semantical Optimization

The main idea behind Latent Semantic Optimization (LSO) is that words with similar meanings are semantically related, regardless of whether they are in the same sentence or paragraph.

For example, “marketing” and “branding” may not sound similar but have related meanings. LSO seeks to identify those words, analyze their context and meaning, and optimize the content for better rankings on SERPs.

Ultimately, LSO strives to provide a more comprehensive understanding of content and allow search engines to rank the website better according to its relevance.


WDF x IDF (which stands for “word document frequency times inverse document frequency”) is a tool used in SEO to analyze the relevance of a particular keyword or phrase. It measures the importance of these words in digital content.

By calculating the number of good-ranking documents for a topic, that are containing a particular keyword and dividing it by the total number of documents containing the same word, one can measure the relevance of that particular keyword. The higher this value, the more relevant a keyword is for that topic.

This metric allows SEOs to determine which words or phrases are most important in order to rank higher in search engine results pages (SERPs). It also helps to identify potential issues with keyword stuffing and provides useful insights into how the content should be optimized.

Keyword Density in Chinese content

The written Chinese language doesn’t know the concept of blank spaces between words. That makes it not easy to distinguish a Keyword Density in the classical sense.

An approach to calculate Keyword Density on Chinese content

Counting the number of appearances of the keyword within the content, multiplied by the number of Chinese Characters this keyword is constructed of, divided by the total number of Chinese Characters within the document, results in a value similar to Keyword Density within western language content.