Keyword Density Checker — Analyze Keyword Frequency Free
Check how often a keyword appears in your text and get its exact density percentage. Analyze single words, 2-word phrases, and 3-word phrases with SEO status indicators, keyword highlighting, and keyword stuffing detection.
How this keyword density checker counts words, phrases, and where they land
Keyword density is a ratio, not a mystery: how many times a term appears divided by the total word count, times 100. The arithmetic is trivial. What makes a density checker useful is everything around that ratio, matching a phrase correctly instead of matching it as a substring of an unrelated word, telling single word terms apart from multi word phrases, and surfacing bigrams and trigrams you never typed into the search box yourself.
All of this runs client side against whatever you paste into the text box. There is no network call, so the content you are analyzing before it is published never leaves your machine.
The core formula
Total word count comes from matching /\b[a-zA-Z']+\b/g against the raw text and lowercasing every match. That regex keeps apostrophes so contractions like don't count as one word, and it ignores numbers and punctuation entirely, which means a table full of digits will not dilute your word count.
How the tool matches your keyword
seo matches seo but not seos or seoing.
/[^.!?]+[.!?]+/g, and each sentence is checked for the keyword so the tool can report exactly which sentences it appears in, up to the first five.
A worked density check
Input: a 92 word paragraph about SEO strategy. Keyword: seo.
| Metric | Result |
|---|---|
| Occurrences | 6 |
| Density | 6.5% |
| Status | Keyword stuffing, above the 2.5% ceiling |
| Density range | Label shown |
|---|---|
| Below 0.5% | Too low |
| 0.5% to 1.5% | Optimal |
| 1.5% to 2.5% | Acceptable |
| Above 2.5% | Keyword stuffing |
Bigrams, trigrams, and stopwords
N-gram tables
Two word and three word phrases are built by sliding a window across the tokenized word list with a helper that joins each consecutive slice with a space, after stopwords and words of two letters or fewer are filtered out, so the phrase tables surface meaningful multi word terms rather than of the or in a.
Stopword list
A fixed list of roughly ninety common English function words like the, and, was, and which is excluded from the single word and phrase tables by default. A toggle lets you include them again if you specifically want to audit filler word overuse.
Matched keyword occurrences are also highlighted directly in your original text using a <mark> wrapped regex replace, so you can scan the passage visually instead of just reading a number.
- Google Search Central spam policies covers keyword stuffing as an anti pattern, not a numeric threshold.
- N-gram background on the bigram and trigram approach used for the phrase tables.
- Stop words explains why common function words are filtered before ranking terms by frequency.
Reading a density number honestly
Checking a blog draft before publishing to make sure your target keyword appears often enough without tipping into stuffing, auditing an old product page that Google flagged for thin or spammy content, comparing density against a competitor’s top ranking page, and finding the natural secondary phrases your own writing already leans on so you can build them into headings deliberately instead of by accident.
FAQ: Keyword Density Checker
Keyword density is the percentage of times a keyword appears in your content compared to the total word count. It matters because it signals to search engines what your page is about. Too low and your page may not rank for the target term. Too high and Google may interpret it as keyword stuffing, which can hurt rankings.
Most SEO professionals target a keyword density between 0.5% and 1.5%. This tool marks that range as Optimal. Densities between 1.5% and 2.5% are flagged as Acceptable but borderline. Anything above 2.5% is flagged as potential keyword stuffing. These are guidelines, not hard rules — context and content quality matter more than hitting an exact number.
Paste your content into the text area, type your focus keyword in the keyword field, and click Analyze Density. This keyword density checker calculates the count, percentage, and SEO status instantly. It also shows where the keyword appears across your sentences.
Keyword stuffing is the practice of overloading a page with a target keyword to manipulate search rankings. Google’s algorithms detect it and can penalise or demote pages that do it. The safest fix is to replace some exact-match occurrences with synonyms or semantically related phrases, and focus on making the content genuinely useful.
Yes. Enter a multi-word phrase in the keyword field and the checker counts exact-phrase occurrences and calculates its density. The frequency tables below also break down the most common 2-word and 3-word phrases in your text, which helps you spot unintended repetition or identify natural long-tail opportunities.
Yes. This keyword density checker is completely free with no word or usage limits. No account required. Everything runs in your browser so your content is never uploaded to a server.
From the blog
Writing about writing tools
Readability scoring, keyword density and the rest, examined properly.
