Keyword density describes how often a target keyword appears on a page relative to its total length, calculated as the number of times the keyword appears divided by the page's total word count. A 1,000-word page using its target keyword ten times has a 1% keyword density.
There's no verified "ideal" percentage Google actually uses, and the metric matters less today than it did in SEO's earlier years, when keyword count alone carried real ranking weight. What Google actually evaluates now is topical relevance and natural language use, not a target ratio to hit, which is why obsessing over density can backfire: a page kept to a specific target percentage often reads awkwardly, repeating a phrase past the point that sounds natural. The more useful frame is writing content that genuinely, thoroughly covers a topic, using the target keyword and its natural variations wherever the writing actually calls for them, rather than treating density as a number to engineer toward.
