Keyword Density

Nearly all search engines try to find keyword density. Some will simply see the first 200-400 characters of your website, and count the number of times the keyword shows. Few index a little amount of text from the top, middle, and bottom parts of your web page, and search them for keywords. In general keyword density must be in the 6-8% range. Only the repeating of the keyword will not work since some search engines consider grammar structure in their calculations. For a very competitive keyword you can aim a little higher maybe targeting a 10% range; however you must take into concern the search engine may consider this spamming.