Keyword density (KWD) is a way to measure how many times you use your key phrase in your content. Basically, if you’re trying to optimize for a specific phrase, say, “leather dog leashes”, then you need to use your key phrase in many places of your Web page. If you don’t use your key phrase effectively in the content, then you aren’t going to be rewarded with a high position on the search engine results page (SERP).

How Do You Measure Keyword Density?

In a simplistic formula, you can think about how many words on your page there are. Divide that into the number of times you use your key phrase, and multiply by 100%. So if you have 500 words on your page, and you use your phrase 5 times, you’d have a 1% keyword density:

5/500 times 100% = 1%

However, as with everything on the search engines, it just isn’t simple. It never is, huh.

Google and the other search engines actually look at all your content in the HTML code, and determine your actual keyword density based on all the places you can put your key phrase:

  • Title tag
  • Description tag
  • Keywords tag
  • Header tag(s)
  • Body Content
  • Menu links
  • Incoming and outgoing links
  • Alt tags on your graphic images
  • Comment tags
  • Div tags

One way to give a quick eyeball measure of your site or someone else’s site, is to use Google’s toolbar. Go to your Web page (or that of a competitor), type in your keyword phrase into the search box, but do NOT click “Search”. Just click the highlighter pen tool, and it will give you a visual of how many times that keyword phrase appears on the page.

Another way to measure your keyword density is to use an online automated tool like the SEO Tools’ free keyword density analyzer tool.

Keyword Stuffing

What is the “right” keyword density? There is plenty of debate, and many SEO professionals say, “stick to the 1-2% range”. The truth is that there is no “right” answer, after all, Google grades on a curve. You can experiment by trying different keyword densities, to see if it helps you or hurts you. Look at your competitors, and I’ll bet that many are higher than 1-2% KWD. I’ve seen as high as 10% or even higher.

However, just remember that if Google counts up all the words on your page, and sees you using your key phrase too often, you may get penalized for overusing the phrase. This is called keyword stuffing, and I say, “Stuffing is great in turkey, but it sucks on your Web site.”

It’s also difficult to come up with creative ways of using your keyword phrase in effective content without sounding ridiculous. It’s better to just write naturally, and not worry too much about it. Use synonyms, antonyms, and other related words in your content. It will help the overall “score” that Google will assign to your page of content.

Image “Optimization”

Some people believe that stuffing your keywords into any nook and cranny on your site that you can think of is a good thing. A common practice is to cram your keywords into the “alt” tag on your images. It doesn’t change the readability of the content, but it can add to KWD. I have a problem with this on two levels:

  • Alt tags are intended to identify the image, especially for the visually impaired or those who use alternative browsers (or just have graphics turned off)
  • “Cheating”, even just a little, may or may not really help you. Writing effective content and just using alt tags for their intended purpose is a best practice.

So if you have a picture of a puppy on your site, just label it:

<img src="/images/puppy.jpg" alt="Photo of a puppy playing." />

Rather than trying to cram your keywords into the alt tag, like alt=”leather dog leashes” from the example above. Those who actually see the alt tag will thank you, and my belief is that Google will “thank” you as well by rewarding your quality content, rather than just trying to cheat a little.