Well-researched, targeted keywords placed within your content are vital to the ranking of your web site. But search engines look at more than just your content. It is important to carefully shape your link profile as well. One of the essential factors in your linking strategy is the use of judiciously chosen keywords in your inbound links. Though almost any link is a good link, your inbound link strategy should include attention to keyword content and variance.

In order to achieve high rankings for your given keywords, it is necessary to demonstrate to the search engines that your page is relevant to the topic. Various on-page factors go a long way to establish this relevance, but search engines, especially Google, give a high degree of importance to off-page factors as well. This can be frustrating, as you naturally have less control over these off-page factors. However you can have a significant effect on your inbound link profile, and it is well worth your time and effort to try.

The most important concept to understand is that of keyword relevance in inbound links. Search engines count inbound links to a web page as “votes” for that page. The more links to a page, the more important it is in the eyes of the search engines. For example, Amazon.com has millions of inbound links, and ranks first in Google for the phrase “books for sale.” However, it does not rank in the top ten for the phrase “car parts for sale”, despite having more inbound links than any of the ranking sites. Why? Google analyzes the text of the inbound links to Amazon (known as “anchor text”), as well as the content of the sites linking to Amazon, and determines that they are highly related to books, not to car parts.

Thus we can see the importance of the the anchor text in inbound links: this text informs the search engines of the subject of our page. If the inbound links indicate that our page is about car parts, and our content is rich with keywords relating to car parts, the search engines get the signal we want to give. Conversely, a page about car parts with lots of incoming links with anchor text such as “click here to learn about chewing gum flavors” will simply confuse the engines. Your link profile needs to be consistent with your on-page keywords and content.

However, while search engines are robots, they are smart ones. If your car parts page suddenly has 10,000 inbound links with the same anchor text, such as “click here for the best car parts,” your link profile looks unnatural. Search engines use sophisticated algorithms to determine whether your link profile looks natural or whether you are trying to game the system. One of the primary factors in a natural link profile is keyword variance. Think about it: if 10,000 webmasters independently decided to link to your page, they would be likely to use a variety of anchor texts. It is vitally important that your link-building efforts mirror a natural link profile.

While the search engines have their own idea of how much keyword variance indicates a natural link profile, a reasonable rule of thumb is that no more than 50% of your inbound links should contain your primary keyword, with the remaining 50% split between about four secondary keywords. This is by no means a hard and fast rule, but it should keep you from having an obviously artificial profile. In addition, to the degree to which you have control, you should make an effort to trickle out your inbound links over time. This too indicates a natural profile.

Despite the attention you should pay to inbound link anchor text, do not underestimate the power of sheer numbers. Massive numbers of links will positively affect your rankings, as long as they are not obvious spam. Links from relevant sites are always valuable, even with generic text. For example, if your car parts page receives an inbound link from a major automotive web site, you will definitely rank better for your keywords, even if the link's anchor text is “click here.” Search engines are smart enough to parse the site that links to yours, and give you credit for a car-related link. However, if you ask for and receive a keyword-rich link, it will send a much stronger signal, and be much more beneficial.

Getting these beneficial, relevant anchor text links can be challenging. Your strategy may be a combination of industry contacts, article marketing, content marketing, linking from your own sites, press releases, and other methods. However you are able to achieve relevant inbound links, it it time and effort well spent. Give the search engines strong relevance signals within a natural link profile, and your rankings will show the difference.