Word Frequency Analyser
Free word frequency analyser, text keyword analyser and keyword density checker. Paste any text to see word and phrase frequency ranked by count, keyword density percentage, 2-gram and 3-gram analysis, stop word filtering and SEO over-optimisation warnings. Export results as CSV.
Analyse Word & Keyword Frequency in Any Text
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What Is Keyword Density and Why Does It Matter for SEO?
Keyword density is the percentage of times a specific word or phrase appears in your content relative to the total word count. It was historically used as a simple signal of what a piece of content was about. Today, search engines use much more sophisticated signals, but keyword density remains a useful diagnostic for avoiding two problems: keyword stuffing (too high) and under-optimisation (too low).
How to calculate keyword density
The formula is simple: Keyword density = (Keyword count / Total word count) x 100. For example, if the word "marketing" appears 15 times in a 750-word article, its density is (15/750) x 100 = 2%. For multi-word phrases (2-gram or 3-gram), count the number of times the exact phrase appears divided by the total word count.
Keyword density vs keyword frequency
Keyword frequency is the raw count of how many times a word appears. Keyword density is the percentage. Both are useful: frequency tells you the absolute count, density normalises for document length so you can compare across different-length pieces of content. Use frequency to identify the most common words; use density to assess whether a specific keyword is over- or under-represented relative to your total content.
What Is 2-Gram and 3-Gram Analysis?
N-gram analysis counts sequences of consecutive words. Most keyword density tools only count individual words (1-gram), missing the fact that most SEO target keywords are multi-word phrases. This tool analyses 1-gram, 2-gram and 3-gram frequencies simultaneously.
| N-gram type | What it counts | Example | SEO use case |
|---|---|---|---|
| 1-gram (unigram) | Individual words | "marketing", "content", "SEO" | Check single-word keyword density |
| 2-gram (bigram) | Two consecutive words | "content marketing", "SEO strategy" | Most common target keyword length |
| 3-gram (trigram) | Three consecutive words | "search engine optimisation", "content marketing strategy" | Long-tail keyword density checking |
Why 2-gram and 3-gram analysis matters: If your target keyword is "content marketing strategy" (a 3-gram), checking its 1-gram components will misleadingly count every appearance of "content", "marketing" and "strategy" individually. The 3-gram tab shows you how often the exact phrase appears, which is the correct figure for keyword density calculation.
Stop words and why you should filter them
Stop words are high-frequency words like "the", "a", "and", "is", "in", "of", "to" that appear in virtually all text but carry little semantic meaning. Without filtering, they dominate any word frequency list, obscuring the meaningful content words. Enable the stop word filter (on by default) to exclude these words and focus on the words that actually signal what your content is about. Disable stop word filtering only if you need a complete unfiltered frequency count for linguistic research or other non-SEO purposes.
TF-IDF: Beyond Simple Keyword Density
TF-IDF (Term Frequency-Inverse Document Frequency) is a more sophisticated measure of word importance than simple keyword density. It accounts not just for how often a word appears in your text (TF), but also for how common the word is across all documents in general (IDF). Words that appear frequently in your text but rarely in general language get a high TF-IDF score, indicating they are meaningful signals of what your content is specifically about.
| Measure | Formula | What it tells you | Limitation |
|---|---|---|---|
| Keyword density | Count / Total words x 100 | How often a word appears relative to document length | Doesn't account for word rarity in general language |
| TF (Term Frequency) | Count / Total words | Same as keyword density (as decimal) | Same as keyword density |
| IDF (Inverse Document Frequency) | log(Total docs / Docs containing word) | How rare or common the word is across all documents | Requires a corpus of documents to calculate |
| TF-IDF | TF x IDF | Importance of a word in this document vs general language | Requires a large reference corpus for accuracy |
The word frequency analyser above shows a relative TF-IDF indicator based on a built-in list of approximately 500 of the most common English words. Words on that list receive a lower effective TF-IDF score because they are common in general language. This gives a practical approximation without requiring a full document corpus.
How to Use a Word Frequency Analyser
SEO keyword density audit
Before publishing any content, paste it into the analyser and enter your target keyword in the Target Keyword field. The tool will highlight the keyword's density and flag any over-optimisation above 3%. Switch to the 2-gram and 3-gram tabs to check the density of multi-word target phrases, which most keyword density tools miss.
Content editing and readability
The 1-gram frequency table immediately reveals overused words in your writing. If a specific word appears far more frequently than others, it may make the content feel repetitive. Use the frequency table to identify which words to replace with synonyms to improve variety and readability.
Academic writing and plagiarism avoidance
In academic writing, word frequency analysis helps identify when you have relied too heavily on the vocabulary of a source. A high frequency of unusual domain-specific terms in your word frequency list may indicate over-reliance on a particular source's phrasing.
Competitor content analysis
Paste a competitor's page content into the analyser to see which keywords and phrases they are targeting and at what densities. Compare the 2-gram and 3-gram results against your own content to identify gaps where competitors are targeting phrases you are missing.