Great content gets clicks not keyword stuffing and search engine spamming, well not for long.
I will probably be using the words 'Search Engines' a lot in this tip, so from now on we'll call them SE's.
So keywords are the… key? Of course no one is going to find a site that offers web design if those two words are never mentioned in the content of the site. So it used to be if you wanted to rank high for 'web design' you would just have those words appear in your site as many times as possible. No need to worry about any real readable verbiage, just 'stuff' the page full of these words. Whomever had the most occurances, would rank the highest. Well that was a long time ago, SE's are so much more sophisticated now. And because of stunts like this they have to be. I remember in the late 90's sites would spam search engines with keywords repeated over and over in a certain page and to keep it from looking too strange to human readers, they would color the text the same as the background. We didn't notice it but SE's did. It worked, for a while. Soon SE's realized what was going on and if the text and BG was the same color, they were ignored.
So brings me to the point of this Tip-O-The Day. Keyword density is a balancing act. Too little will reap no ranking rewards and too much may actually hurt your ranking. If Google or Yahoo! thinks you are pulling a fast one because half of the text on your page consists of a certain word, not only will they ignore this page, but if you had any decent ranking on this page prior to these changes, you will be penalyzed. You will see that ranking drop.
The sweet spot appears to be around 5-7 percent, while going over 10 percent may be perceved by SE's as SPAM. So keep this in mind when you author your next web page. Decide what keywords you want to target, sprinle it around but keep it in these ranges. There are many free, online, sites that will give you the keyword density, just do a search I am sure you will find more than a few dozen.
Why would these percentages be the target. Well first of all I want to make it clear that no one knows for certain how any of this works, they are mostly educated guesses based on SE experiments. The recipe for ranking websites is a highly guarded secret of SE's and probably no single person knows the whole recipe. But you can arrive at a very good guess by measuring changes you make on your site and watching the ranking. This seems to be the range most people agree on. You want the density to be very high without it appearing as though you are keyword stuffing, SE's won't like your page, they want it to be relevent and readable. If you find a way to trick SE's, it may work for a while but you are asking for trouble. It is not uncommon for domains to be banned from SE's for shifty SEO practices.