Keyword Density Checker

How Keyword Density Checker Works

This tool counts how often each word or phrase appears in a block of text and shows what share of the total word count it makes up -- its "keyword density." It's meant as a quick sanity check before publishing, to spot a phrase that's repeated so often it might read as keyword stuffing, or to confirm a target keyword actually appears often enough.

Formula & Method

Text is tokenized into lowercase words (letters, digits, and apostrophes only). Depending on the segmented control, the tool counts single words, 2-word phrases, or 3-word phrases (n-grams) by sliding a window across the token list. With "Exclude common stop words" checked, single words that are in a built-in stop-word list (the, a, and, of, is, and similar) are skipped, and for 2- and 3-word phrases, any phrase starting or ending with a stop word is skipped -- the middle word of a 3-word phrase can still be a stop word. Density for a phrase is (occurrences × phrase length) ÷ total words × 100, and only the top 15 most frequent entries are shown.

Worked Example

The sample text loaded by default is 56 words long. With single words and stop-word exclusion on, "content" appears 8 times for a density of 14.3%, "seo" appears 3 times for 5.4%, and "keyword" appears 2 times for 3.6%. A density around 14% for the main topic word is quite high by typical SEO guidance (often 1-3% is recommended), which is exactly the kind of thing this tool is designed to flag before you publish.

Frequently Asked Questions

What keyword density percentage is considered good for SEO?

There's no single official number, but a commonly cited guideline is keeping a target keyword's density roughly in the 1-3% range -- high enough to signal relevance, low enough to avoid looking like keyword stuffing to both readers and search engines. Search engines themselves don't publish an exact target, so treat any percentage as a rough guide rather than a strict rule.

Why does switching to 2-word or 3-word phrases change which stop words matter?

For phrases, only the first and last word are checked against the stop-word list -- a 3-word phrase like "content that reads" keeps "that" in the middle even with stop-word exclusion on, since removing every phrase containing any stop word would filter out too many legitimate phrases.

Does the tool distinguish between different forms of the same word (e.g. "content" vs "contents")?

No -- each exact word form is counted separately. "Content" and "contents" are treated as two different words with their own separate counts, so density figures reflect exact-match frequency, not stemmed or lemmatized word roots.

Why is the list limited to the top 15 entries?

Showing every unique word or phrase in a long piece of content would make the results unreadable, so the tool keeps only the 15 most frequent entries -- which are also the ones most relevant to spotting over-repetition or confirming keyword usage.