What does it do?
Counts the number of links found pointing to this website, and compares them against other sites.
Why is it important?
The volume of quality links correlates highly with how well regarded a website is by search engines. Websites with many links generally score far higher. Link building (i.e. purposely obtaining links to a website) is a large part of effective Search Engine Optimization.
Links are also an excellent means of measuring how prominent the website is on the Internet – i.e. prominent websites will generally attract more links all by themselves.
How is it measured?
The number of links counted by SEOmoz’s Open Site Explorer are measured. Higher numbers of links count towards a higher score. Sitebeam only counts links that SEOmoz has identified as “juice passing” links, and thus this number may not match up exactly with what you see while using the OSE.
The score is determined by the MozRank of the site.
The score is calculated on a logarithmic scale. The numbers of links and the places they come from are used to determine the MozRank. This mirrors (approximately) the behavior of Google’s PageRank.
If a website is new, it can take some time to find links to it. If the website has very few incoming links, there is a chance this test will not find them.
It is not possible to count every possible link from every possible website. Like Google, this test cannot search the whole Internet instantly on demand. Instead it checks an index it has built of the majority of the Internet, which is being constantly updated. As a result, like Google, results will always be approximate.
Also, the number of links reported by different search engines (Google, Bing, Yahoo etc) will vary from this count and each other. There is no consensus on how links should be counted.
For example, Google is much pickier at counting links, but the links they do count are of higher value. Among other criteria, Google generally exclude links that:
- Come repeatedly from one website (e.g. in the footer of every page)
- Come from a set of related webservers (e.g. similar / identical IP addresses)
- Come from a set of websites which appear to reference each other exclusively
- Come from sites that reciprocate the link
- Come from blacklisted websites
- Come from brand new websites
- Come from websites filled with some user generated content (e.g. Wikipedia)
- Are invisible or nearly so (e.g. white text on white background)
In effect, Google are very good at eliminating most of the common tricks for generating artificial links, which people have used to trick search engines in the past. All link counts use some variation of this approach, and these approaches are usually kept secret.
Therefore, you should not consider this test an absolute metric, but a relative one. You can use it to say website A has more links than website B, but you shouldn’t ascribe precise value to a specific number of links. The value in this information is in how it compares with other sites, not how high the number is.
How to improve this score
Obtain more quality links to your website (see link building).
How to use this test effectively
If the score for this test is low, consider investing in link building. The resulting increase in search engine placement is likely to be considerable. Otherwise we recommend people check the number of links they have, and that it is always increasing (this should happen automatically, as nearly all websites accumulate more links over time).