Before 2011, keyword inclusion in your content and meta tags was a nearly surefire way to ensure that a page of your site ranked for that specific keyword.
This is where the concept of “keyword density” came in, with some sources recommending a density of two or three percent on any given page (meaning two or three percent of words or phrases within the body of your content were your exact target keywords). Then, the Panda update came and everyone started questioning whether density was still a thing; was it better to include that specific number of keywords, or focus on creating great, user-focused content?
That question remains today, but it’s only grown more complicated. The emergence of the Hummingbird update (and subsequent semantic search improvements) has prompted new research, and it suggests that, perhaps, body-level keywords aren’t as important as they used to be.
Relevance and Authority
Before I get into too many specifics, I want to examine the twin indicators of rank: relevance and authority. In the abstract sense, relevance is how likely your site is to address a user’s needs, and authority is how trustworthy your site is overall.
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.
Thus, the goal with keyword density was to prove to Google that your page was relevant for a phrase like “ice cream parlor,” by including the phrase “ice cream parlor” throughout your content.
The Hummingbird Update
Why is that important? Because the Hummingbird update changed how Google views relevance.
Rather than looking for exact-match keywords, Google now attempts to understand the intent behind a user’s query, and finds pages that match that intent. For example, rather than looking for instances of “ice cream parlor” on pages online, Google looks for pages that demonstrate qualities that an ice cream parlor would have, speaking contextually about ice cream parlors using natural, conversational language.
This implies that keyword inclusion isn’t nearly as important as simply writing about the right subjects—and relying on natural language to take care of the rest.
But is that the full picture?
The Latest Research
The latest research from SEMRush, analyzing ranking factors in 2017, suggests that exact keyword inclusion may not matter as much as it used to. One section of the report focused exclusively on how keywords were used in the title, meta description, and body of various pages, compared to how those pages ranked for those keyword queries.
Overall, the higher the search volume for a given keyword, the more correlated it was with being featured on a ranking page. That means high-volume keywords were more likely to appear in titles, descriptions, and the body of pages that ranked high for those queries.