Keyword Density Analysis
Once you have selected the keywords you wish to target, it's time to analyze your use of them on your pages. Keyword density is the ratio of keywords or keyphrases to the total number of words on a page. For example, if you were to use your keyword once for every 100 words, the keyword density would be 1%. In order to get the best results, you should aim for a keyword frequency of between 1% and 7%.
It's very important to stay within the suggested range; too low use of a keyword might be indicative that your page lacks in detail pertaining to the topic, raking it as not relevant enough, while overusing a keyword can raise a red flag in the search engines suggesting that your site is over-optimized. So, without having to say much it's evident that keyword density analyzers can be quite useful. Consult the list at the bottom of the page for links to free tools.
What a keyword analysis tool allows you to do is to write natural content, without forcing yourself to use a particular keyword or phrase every so often; this usually produces much better content. Once you are finished writing, you can then analyze your page for keyword spread and frequency. You may find that you have repeated certain words too much and not used others often enough. The keywords should be spread out throughout the page in a natural manner, avoiding too much repetition in one particular are on the page. Stuffing all of your keywords in one after another will seem spammy to many search engines causing your site to be thrown out or not be indexed at all.
Another especially important point is that your keyword usage should look natural to your readers in terms of reading well. Many people will pick up on your optimizing techniques if you stuff your keywords in where they don't seem to fit and will not take your site seriously enough to stay. And while we're talking about natural looking keywords, try to toss up your titles a little. Don't just put your keyword term alone as your title every time - try to be a little more creative and add some other descriptive words to the mix! This will make the page look more natural to the search engines and your readers. Your readers are, after all, more important than the search engines, especially since search engines are starting to take into account how long people stay on your pages as well.