How to Check Keyword Density (and What It Is Actually Good For)
Let me save you some time: keyword density is not a Google ranking factor, and chasing a magic percentage is a 2009 move that can actively hurt you. If someone sells you a "perfect 2.5% density" rule, be suspicious.
And yet I still check it on most things I write. Not to hit a number, but because the density figure is a fast, honest mirror that catches two real problems. Here is how to measure it and, more importantly, how to read what it is telling you.
What keyword density actually is
It is just how often a word or phrase appears, as a percentage of the total word count. If "api tester" shows up 8 times in a 400-word page, that is 2% density (counting it as two words, 16 of 800... but nobody agrees on whether to count phrases as one term or several, which is your first hint that the precise number is not sacred).
Paste your text into the text analyzer and it ranks your most frequent words and their density automatically, alongside word count, sentence count, and reading time. It runs in your browser, so nothing you paste is uploaded.
The two things it genuinely catches
1. Over-optimization (keyword stuffing). If your target phrase is sitting at 5% or 6%, your writing almost certainly reads like a robot wrote it for Google, and modern search is very good at spotting that. High density is a warning light, not a target. When I see it, I rewrite until the phrase appears because it needs to, not because I forced it.
2. You forgot to mention your own topic. The opposite problem is more common than people think. You write 1,200 words about "image cropping" and your main phrase appears twice, buried, while filler words dominate the frequency list. That is a sign the page is not clearly about what you think it is about. Density near zero on your core term is the real bug.
So what number should I aim for?
None, honestly. Aim for "reads naturally to a human." If you must have a sanity range, a core phrase landing somewhere under ~2% in long content is usually fine, but I would not lose a minute optimizing between 0.8% and 1.5%. Spend that energy on related terms instead: a page about "keyword density" should also naturally mention checkers, word frequency, SEO, and over-optimization, because real topical coverage beats repeating one phrase.
A faster way to use it
Write the thing first, ignoring keywords entirely. Then paste it into the analyzer and look at the top 10 words. Two questions: is my main topic actually near the top? And is anything suspiciously high? If the answer to both is "no problem," you are done. That 30-second check is the entire value of keyword density in 2026. Everything beyond it is busywork.
FAQ
Is keyword density a ranking factor?
No. Google does not rank by a density percentage. It is useful as a check for over-optimization and for confirming your page is clearly about its topic, not as a target to hit.
What is a good keyword density?
There is no magic number. Write naturally. If a core phrase creeps above ~2-3% in long content, that is usually a stuffing warning, not a win.
How do I check it for free?
Paste your text into the text analyzer. It shows word frequency and density in your browser, with nothing uploaded.
Run the 30-second check now in the free text analyzer, or see the rest of our free browser tools.