What is Keyword density?

Keyword density measures how often a word or phrase appears in a piece of text compared with the total number of words. It is a simple ratio, usually expressed as a percentage, and it was once treated as a dial you could turn to rank higher. That era is long gone, but the metric is still a useful diagnostic when you read it correctly.

The formula

density (%) = (times the phrase appears ÷ total words) × 100

Example: a 1,200-word guide mentions "trail running shoes" 9 times
9 ÷ 1,200 × 100 = 0.75%

Tools differ on details. Some count a three-word phrase as three words in the numerator; others count it once. Some remove stop words such as “the” and “of” before counting. That is why two checkers can report different percentages for the same page — compare figures from one tool only.

There is no ideal percentage

You will see advice like “aim for 1–2%”. No search engine has ever published a target, and modern ranking systems understand synonyms, related terms and topics rather than counting exact repetitions. A page about trail running shoes that also talks about grip, drop, cushioning and terrain is clearly about the subject, even if the exact phrase appears only a handful of times.

The real risk sits at the high end. Google’s spam policies list keyword stuffing — repeating words or phrases so often that it sounds unnatural, or out of context — as a violation. Readers notice it before algorithms do.

How to use density as a diagnostic

• Spot stuffing. If one phrase towers over everything else in the list, read the text aloud. Repetitive sentences need rewriting.
• Confirm focus. Your page’s main topic should show up among the top two- and three-word phrases. If the top phrases are navigation labels or cookie-banner text, your main content may be too thin, or boilerplate dominates the page.
• Check placement. Frequency matters less than position. The main phrase, or a close variant, belongs in the title, the H1 and the meta description, where it tells both searchers and engines what the page covers.
• Find vocabulary gaps. Compare your top phrases with those on pages that already rank. Missing subtopics usually show up as missing phrases, which also points you to long-tail keyword variations worth answering.

Common mistakes

Forcing an awkward exact-match phrase into every paragraph (“best plumber Chicago cheap”), padding pages with synonyms just to hit a number, and optimizing density while ignoring search intent — a perfectly “dense” product page will not rank for a query where people want a how-to guide.

How to check

Paste a URL or text into the Keyword Density Checker. It lists the top one-, two- and three-word phrases with counts and density, removes stop words in English, French, Spanish and Arabic, and shows whether your main phrases appear in the title, H1 and description. Use it alongside a wider on-page SEO review rather than as a target to hit.

Frequently asked questions