liminfoKeyword Density Checker
Free web tool: Keyword Density Checker
About Keyword Density Checker
The Keyword Density Checker analyzes any block of text and computes the frequency and percentage density of every word and phrase it contains. Paste your article, blog post, product description, or any other content into the text area, and the tool immediately tokenizes the input — converting it to lowercase, stripping punctuation, and splitting on whitespace — to produce a ranked frequency table. You can switch between single-word, 2-word phrase (bigram), and 3-word phrase (trigram) analysis tabs to understand which terms dominate your text at different levels of granularity.
SEO writers, content strategists, and digital marketers use keyword density analysis to ensure their target keywords appear at an appropriate frequency without over-optimizing. Traditional SEO guidance suggests a keyword density of 1–3% for primary terms and lower densities for supporting phrases. The bigram and trigram views are especially useful for identifying LSI (Latent Semantic Indexing) keywords and natural language phrases that search engines associate with your topic.
The analysis algorithm supports both Korean (Hangul) and English text, using a unified regex that handles Unicode Korean character ranges alongside standard alphanumeric words. You can set a minimum character length filter to exclude very short words like prepositions and articles, which tend to dominate raw frequency counts but carry little SEO value. Results update live as you type or paste, and you can load more results beyond the initial top 30 to see the full distribution.
Key Features
- Single-word, 2-word bigram, and 3-word trigram frequency analysis in three separate tabs
- Keyword density percentage calculated as word count divided by total word count
- Minimum character length filter to exclude stop words and short function words
- Visual bar chart column showing relative frequency compared to the top result
- Ranked table with position, keyword, raw count, and density percentage columns
- Live total word count display that updates as you type or paste
- Load More button to display results beyond the initial top 30 entries
- Full Korean (Hangul) and English language support with Unicode-aware tokenization
Frequently Asked Questions
What is keyword density and why does it matter for SEO?
Keyword density is the percentage of times a specific keyword appears in a text relative to the total word count. For example, if "coffee" appears 5 times in a 500-word article, its density is 1%. SEO practitioners monitor keyword density to ensure their primary terms are present enough to be recognized by search engines without triggering over-optimization penalties.
How is keyword density calculated in this tool?
The tool divides the number of occurrences of each word or phrase by the total number of words in the text, then multiplies by 100. Total word count is based on all words meeting the minimum character length threshold, not the raw word count before filtering.
What is the difference between bigrams and trigrams?
A bigram is a 2-word consecutive phrase (e.g., "digital marketing"), while a trigram is a 3-word phrase (e.g., "search engine optimization"). Analyzing bigrams and trigrams helps identify multi-word keyword phrases that often carry more SEO specificity than single keywords.
What keyword density is recommended for SEO?
Most SEO practitioners aim for 1–2% density for primary keywords and 0.5–1% for secondary keywords. Very high densities above 3–4% can be flagged as keyword stuffing. However, modern search engines focus more on topical relevance and natural language than strict density ratios, so these figures should be treated as guidelines rather than hard rules.
How does the minimum character filter work?
Setting the minimum character length to 2 (the default) filters out single-character words. Setting it to 3 or higher also removes short 2-letter words like "is," "in," "at," and "의," "이," in Korean. This makes the frequency results more meaningful by focusing on substantive content words.
Does this tool support Korean text analysis?
Yes. The tokenizer uses a regex that matches both standard ASCII word characters and Korean Hangul characters (Unicode ranges ㄱ-ㅎ, ㅏ-ㅣ, 가-힣). Korean words are treated the same as English words for frequency counting, and the minimum character length filter applies to the character count of each token.
Can I analyze very long texts like full articles or book chapters?
Yes, there is no hard character limit on the text input. However, very long texts may take a fraction of a second longer to process as the tool builds frequency maps for potentially thousands of unique words and phrase combinations. The initial display shows the top 30 results per tab to keep the interface fast.
Is the analysis data sent to any server?
No. All text processing happens entirely within your browser using JavaScript. Your text is never uploaded, stored, or transmitted to any server. You can safely analyze confidential drafts, proprietary content, or unpublished articles without any privacy concerns.