Keyword density refers to the amount of times a word or phrase occurs within any given page. The keyword can appear in a number of places, for instance:
Page Title, Meta Description, Meta Keywords, Visible Text, Alt Tags, Comment Tags, Domain Name, Image tags, Linked Text, Option Tags and Reference_Tags. Each search engine prefers different density to each other and there is no formula to go by, only some recommendations which will follow.
Most website owners talk about their most important keywords, but very few really do anything about how they use them within their content and expect to feature well in the search engines. These often overlooked search terms that are so important to a website’s placement in the search rankings are a vital component of any search engine optimisation (SEO) effort.
Without keywords for the search engines to index, there is literally nothing to find in the search engine results pages (SERPs). Keywords are the whole purpose of the search engines crawling your site and it is these terms that will potentially lead customers to your site.
Location and Density of Keywords:
There are both “on page” and “off page” factors to be considered when optimising a site for keyword density. As you can see from the list above, keywords are gathered from numerous places and each search engine calculates its keyword relevancy formula in different ways.
Some permit heavier use of keywords on a page than others and some attach more importance to position on a page and page title text. Some engines, like Google, prefer to see much lighter use of keywords to discourage over use, or what is referred to as search engine spamming.
Other on page keyword modifications that carry great weight are bolding, italic, and actual keyword type size used. Other factors include the use of page titles, and their relative importance to the various search engines, as keyword delivery mechanisms. Care must also be taken when creating or requesting links into your site, the anchor text used to link through to the site is actually collated and seen as on page content for your site and must therefore have some relevance to the content it refers.
Once a good balance of both the placement and density of a web page’s keywords is created, you will see a marked difference in performance in the search engines when compared to a site that has not been optimised. Whilst there is no secret formula, common
sense and good search engine practices will harvest great results.
When planning which keywords to target on a page, a plan of attack must first be devised. Never dilute your message by having too many keywords focused on one page, divide your site into sections and theme each section on one keyword. If the keyword is not that competitive, maybe two, but I always recommend optimising for one keyword per page.
Keep the long term goal in mind of ranking high for a particular keyword or keyword phrase. To score highly for that selected search term, a concentrated effort is essential. Think one keyword, with accompanying phrase, maximum for each page. In a competitive search field, the single keyword approach is the only one worth employing, if you want to rank well at all.
The site’s home page and internal pages should have slightly different focus, but they should be created with the overall goal in mind and be highly relevant. This is especially important for highly competitive keyword situations. Since low, medium, and highly competitive keyword conditions require differing strategies, they need individual consideration.
Each targeted keyword should then be provided with separately linked and themed internal supporting pages. By providing additional theme and topic related pages, the keywords are given extra support, and overall on and off page density is increased.
The objective is to create a powerful website theme built around that single keyword. Anything less, and the site will not be able to compete for that term at all. Regardless of the level of competition, it’s a good idea to become dominant in as many search terms within the site’s topic as possible. Once top search rankings are achieved with an important keyword, move to the next one. The more keywords are controlled, the more paths are available to enter the website, resulting in huge increases in visitor traffic, which will in turn help boost your sites rank in achieving better results in other search terms.
Some guidelines to consider:
When deciding how heavily to place keywords on a page, there are different guides for different search engines, I will always recommend optimising for Google because in my opinion they encourage the best practices, they are less biased by paid results and command the lions share of search traffic.
Google has the strictest requirements regarding keyword density. No more than 2% of a web page’s words should be the targeted keywords. Any more will be considered spamming. On the other hand, Yahoo! and MSN Search have much higher keyword density tolerances, perhaps as high as 5% of total words. That difference leaves quite a distance between the optimum limits for Google and the levels permissible in Yahoo! and MSN. A good optimisation company will realise that a trade off will be necessary, while ensuring that the copy reads well for potential customers and clients and conforms to UK accessibility laws.
The page’s most important keyword is included in the page title. Each web page should have a unique title, providing an extra keyword boost to that page. Titles are a very crucial part of the various search engine algorithms, and are an important way to prominently display the most sought after keyword on the page.
While it is debatable whether placing keywords early in the on page copy is helpful in Google, higher placement does appear to have some benefit in Yahoo! and MSN Search. Those search engines give some additional weight to bolding, italics and text enclosed in H1, H2 and H3 tags as well.