Keyword Density Checker

Paste your content and check the frequency and density of every word and phrase. Single words (1-gram), 2-word phrases, and 3-word phrases are all counted. Keyword density (term count ÷ total words × 100) is shown per term so you can spot over-optimised keywords — above ~4% for a single keyword is a red flag for over-optimisation. Toggle stop-word filtering to focus on meaningful terms.

How to use the Keyword Density Checker

Paste your article or page copy into the text area and click Analyse. Results update live as you type.

  1. The summary bar shows total word count, unique word count, and the top single-word density.
  2. Select the Phrase length to switch between single words, bigrams, and trigrams. All three give different insights.
  3. Enable Filter stop words to exclude function words (the, is, of, and…) so the table focuses on meaningful terms. For raw frequency counts, disable it.
  4. The results table shows: term, count, and density % (count / total words × 100). Single-word terms above 4% density are flagged in orange as potential over-optimisation warnings.

For SEO, aim for your target keyword at 1-3% density. If it\'s over 4%, the copy may read unnaturally and Google\'s quality signals may penalise it. If it\'s under 1%, you may be under-emphasising the topic relative to search intent.

Keyword density: what it is and when it matters

Keyword density is the ratio of how often a specific word or phrase appears in a piece of content to the total word count, expressed as a percentage. A 1,000-word article mentioning "keyword density" ten times has a 1% density for that term. The metric emerged in the early days of SEO when search engines relied heavily on keyword frequency as a ranking signal. While modern search algorithms (Google's BERT, MUM, and RankBrain) understand semantic context and intent far beyond raw frequency, keyword density remains a useful sanity check for content quality.

The practical concern today is not optimising for a specific density target, but avoiding two failure modes: under-optimisation (the page barely mentions the topic it should be about, leaving search engines uncertain of relevance) and over-optimisation (keyword stuffing — mechanical repetition of a term at the expense of readability). Google's Panda algorithm update (2011) specifically targeted pages with unnatural keyword stuffing, and the quality signal has been refined in every major core update since. A density above 4-5% for any single keyword is a pragmatic warning threshold, not a hard rule — context matters.

Phrase-level density (2- and 3-word n-grams) is often more actionable than single-word density. Your target phrase "responsive web design" might appear at 1.2% while the word "design" appears at 3.8% — knowing both gives a more complete picture of topical emphasis. Combined with a TF-IDF analysis, keyword density checking can reveal which terms you over- or under-use relative to a competitor corpus.

Common use cases

  • On-page SEO review — paste a draft article and verify the target keyword and semantically related terms appear at natural, non-spammy frequencies before publishing.
  • Content editing — spot terms you\'ve accidentally repeated too often (e.g. a word that slipped in from copy-paste) and diversify the vocabulary.
  • Competitor analysis — paste a competing page\'s content and see which phrases they emphasise — useful input for planning your own content angle.
  • PPC ad copy review — check that your primary keyword phrase appears at least once in headlines and body copy without feeling forced.
  • Product description audit — e-commerce product copy often suffers from keyword stuffing pushed by non-technical teams; flag over-optimised terms before they hurt rankings.

Frequently asked questions

What keyword density should I aim for?
There is no universally correct percentage. A natural 1-2% for your primary keyword and broader coverage of related terms is a safe guideline. More important than density is that the keyword appears in the title, H1, first paragraph, and at least one subheading. Focus on readability first; density is a check, not a target.

Is keyword density still an SEO ranking factor?
Not directly — Google hasn't used raw keyword density as a direct ranking signal for years. However, it remains a useful quality proxy. A page with zero instances of its supposed target topic likely ranks poorly; a page with 10% density likely reads as spam. Think of density as a symptom indicator, not a lever.

Why should I check phrase density (bigrams/trigrams) as well as single words?
Multi-word phrases capture the exact terms users search for. "Machine learning" means something very different from "machine" + "learning" separately. Bigram density tells you how often your exact target phrase appears, which is more actionable for on-page optimisation than single-word counts.

What are stop words and why filter them?
Stop words are common function words (the, is, and, of, to, a…) that appear in almost every English text and carry no topical meaning. Without filtering, they dominate the frequency list and obscure meaningful terms. Filter them for SEO and content analysis; turn off filtering if you need raw word counts for readability or linguistics work.

How is word count calculated here?
Total word count is the total number of whitespace-delimited tokens after stripping punctuation, including stop words. Unique word count is the number of distinct lower-cased tokens. Density % = (term count / total word count) × 100, computed against the full word count (including stop words), so it reflects real document density.