Aim for Keyphrase Density of 3% - 7%

Keyphrase density is defined as the number of times that a keyphrase appears on a webpage divided by the total number of words on that page. Search engines use keyphrase density to determine whether an article is relevant to a search term. An ideal article will have at least 300 words of text and should have a keyphrase density of 3% to 7%, meaning that the keyphrase should appear 3 to 7 times for every 100 words of copy, with the highest density in the first paragraph. Here is an example:

Each blood donation saves three lives. While 60% of the U.S. population is eligible to donate blood - only 5% do. When asked, the #1 reason for not giving blood is because "no one asked me." Unless you're a multi-millionaire or a medical professional, blood donation probably represents the easiest way for you to save the most lives, every 56 days.

Blood banks often run short of blood-types O and B, particularly during the summer months and winter holidays when regular blood donors are on vacation. Blood shortages cause cancellation of surgery - or worse.

So, if you've got a few hours to help, rather than just donating blood yourself, how about saving even more lives by organizing a blood donation drive at your office, apartment, or dorm?

To give blood, or to organize a blood donation drive, you can contact The Red Cross at 1-800-GIVE-LIFE.

If your keyphrase density is too low (below 3%), search engines may not identify your article as relevant to related search terms. However, if your keyphrase density is too high (above 7%), your article will be difficult for users to read comfortably and may be identified as "spammy." Many search engines can now identify webpages that use an unnaturally high number of keyphrases in a single article or are optimized for one keyphrase without having any of the related phrases that are typically included in similar, naturally written documents.

To determine an article's keyphrase density, use an online density analyzer such as Ranks.NL at http://ranks.nl. Type in any URL and this tool will determine how often each primary and secondary keyphrase appears on the webpage.