On-Page SEO

Keyword Density

The share of a page's words that are a target keyword — a metric modern search does not use.

Keyword density is the percentage of a page's words that are a given keyword. It was a real ranking factor in early search engines and has not been one for many years: modern systems interpret meaning rather than count strings. Writing to a target density reliably produces worse copy without producing better rankings.

Definition

The measure is simply keyword occurrences divided by total words. Tools still report it, and the number can be diagnostically useful at the extremes — zero mentions of the subject, or an implausible twelve percent.

What replaced it is topical coverage: whether a page addresses the subject and the questions around it, in natural language. NLP-based retrieval does not need the exact phrase to know what a page is about.

Why It Matters

Chasing a density target is how pages end up unreadable. The only version of this metric still worth checking is whether the subject is mentioned at all, and whether it has been repeated to the point of awkwardness.

Example

A page mentioning "canonical URL" three times in 1,200 words of clear explanation will out-rank one repeating it forty times in the same space.

Why the metric survives despite being obsolete

Keyword density persists because it is easy to compute and produces a number, and a number feels like a target. Every SEO tool reports it, which keeps it in circulation long after the systems it modelled were replaced.

It was a reasonable proxy in 1998, when relevance was largely term frequency. It stopped being one when retrieval moved to embeddings and entity resolution, which is why no current Google documentation mentions a target density and why writing to one produces text that reads as written for a machine.

The only version still worth checking: is the subject mentioned at all, and has it been repeated to the point of awkwardness? Both are answerable by reading the page aloud, which is a better instrument than the percentage.

How SlapMyWeb checks this

The audit reports word count and whether the page's apparent subject is present in the title, headings and opening content — not a density percentage, because there is no threshold worth reporting. Where density is still diagnostic is at the extremes, so an implausibly repetitive page is flagged as potential keyword stuffing rather than scored on a ratio. Check a page's term distribution with the keyword density checker.