There has always been something intriguing about the concept of keyword density. Many years ago, search engine optimization professionals relied on keyword and phrase density (also called keyword prominence) as one of the core strategies behind top rankings. What made keyword density so appealing is that it was straightforward and simple. The downside is that it was misused if not outright abused. While keyword density remains a bit dated as an SEO tactic in general, there is still plenty of value in revisiting the practice as a means to improve rankings — if you know how to use it.
There are far more accurate (better) ways for search engines to determine true relevance than keyword density, and each search engine has its own means and methods to rank sites for a particular keyword or phrase. Search engines consider usage data, anchor text of inbound links, site/domain age, and general authority (all of which have been discussed here at WM), but each one of these criteria also has its own way of relating/associating keywords and key phrases. This is called natural language processing and is something you, as someone responsible for high site rankings, have an immense amount of control over and should spend time on improving.
The issue is not that keyword density is a bad means to determine relevance; it’s just that search engine algorithms have evolved while many SEOs and the search engine optimization software tools they use, have not. Where keyword density tools fall short is their ability to provide meaningful assessment and objective insights into ranking improvements. But keyword density tools are meaningful when used in conjunction with the right tactic. The “right” tactic in this case is to reduce on-page irrelevance and to boost relevance.
The semantic algorithms of popular search engines typically look at supporting vocabulary when determining the relevancy of a page. The question to ask yourself is simple: If you removed the keyword phrase being targeted from your page, would it be very easy to rank for that term? If search engines can still determine what your page is about with the remaining/supporting text, then the answer is a definitive Yes. Let’s look at a few popular keyword density analyzer tools to see this in action.
Should you want to dig deeper into the relevancy of keywords and pages on your own site (or that of your competitors), then let me know.