Free Online Keyword Density Checker

Why use Keyword Density Checker

• SEO content writers can check whether their target keyword appears at a natural frequency before publishing, avoiding both under-optimization and keyword stuffing penalties.
• Digital marketing teams auditing existing blog content can quickly identify pages where keyword density exceeds recommended thresholds and needs revision.
• Freelance writers delivering SEO-optimized articles to clients can include a density report as proof that the content meets keyword usage guidelines.
• Website owners running their own content strategy can analyze competitor pages by pasting their text to understand which phrases they emphasize most.
• Students and researchers writing academic papers can check whether certain terms are overused, improving the variety and quality of their writing.

How it works

The tool tokenizes your input text by converting it to lowercase and extracting individual words using pattern matching. It then builds frequency maps for three n-gram sizes: unigrams (single words), bigrams (consecutive two-word pairs), and trigrams (consecutive three-word sequences). For each n-gram, the tool counts how many times it appears and divides that count by the total number of possible positions for that gram size, producing a density percentage. When the stop words filter is enabled, any n-gram containing a common English word (articles, prepositions, pronouns, auxiliary verbs) is excluded from the results. The output is sorted by frequency in descending order, with the top 50 results displayed in a table alongside a color-coded density bar: green for under 2%, amber for 2-3%, and red for over 3%.

About this tool

Analyze the keyword density of any text by breaking it into single words, two-word phrases, and three-word phrases using n-gram frequency analysis. This free online keyword density checker is built for SEO professionals, content writers, and digital marketers who need to understand how often specific terms appear in their content relative to the total word count. Keyword density is expressed as a percentage, calculated by dividing the number of times a keyword or phrase appears by the total number of word positions in the text and multiplying by 100. Search engines use keyword frequency as one of many ranking signals, and content that repeats the same phrase too often risks being flagged for keyword stuffing, which can result in ranking penalties. The generally accepted guideline is to keep primary keyword density between 1% and 3%, with supporting keywords appearing naturally throughout the text. This tool helps you identify when a term crosses from natural usage into potential over-optimization territory. Paste any text into the input area and the tool instantly generates a ranked table of the most frequent terms across three n-gram sizes. Unigrams show individual word frequency, bigrams reveal common two-word combinations, and trigrams surface recurring three-word phrases that might indicate repetitive phrasing or topical emphasis. Each result row displays the raw count, the density percentage, and a visual bar so you can spot outliers at a glance. A built-in stop words filter lets you toggle common English words like articles, prepositions, and pronouns on or off, which is useful for focusing on meaningful content keywords rather than grammatical filler. Results can be copied to clipboard or exported as a CSV file for further analysis in a spreadsheet. The density guide at the bottom of the results explains the color-coded thresholds: green for natural usage under 2%, amber for moderate density between 2% and 3%, and red for densities above 3% that may indicate stuffing. All processing runs entirely in your browser, so your content is never uploaded to a server.

How to use Keyword Density Checker

1. Paste your text. Copy the article, blog post, or web page content you want to analyze and paste it into the text input area.
2. Choose your n-gram size. Select Single Words, Two-Word Phrases, or Three-Word Phrases using the tabs above the results table to view different levels of keyword analysis.
3. Toggle stop words filtering. Check the Exclude stop words box to remove common English words like 'the', 'and', and 'is' from the analysis, focusing on meaningful content keywords.
4. Review density percentages. Examine the density column and color-coded bars. Green indicates natural usage under 2%, amber signals moderate density between 2-3%, and red flags potential keyword stuffing above 3%.
5. Export your results. Click Copy to copy the results as tab-separated text, or Export CSV to download a spreadsheet-ready file for further analysis or reporting.

Use cases

• A content marketing manager at an agency runs every client blog post through the checker before publishing to verify that the target keyword stays between 1% and 2.5% density.
• An SEO specialist auditing a 50-page website pastes each page's content into the tool and exports CSV reports to build a keyword density audit spreadsheet.
• A freelance copywriter uses the bigram analysis to identify whether the two-word product keyword appears enough times in a product description to support ranking.
• A small business owner writing their own website copy checks trigram density to make sure they are not repeating the same three-word phrase unnaturally throughout a service page.
• A content strategist analyzes competitor articles by pasting their text to discover which phrases they emphasize most heavily and at what density levels.