A Link Too Far: Understanding Link Depth Origination

It’s become easier to find the links pointing to your site, thanks to wonderful tools like LinkPopularity.com or by using the [link:URL] search, which works on several search engines. Click here for an example from Google: link:http://www.URLwire.com.

There are some major flaws with using search engines to find the links pointing to your sites, and link popularity worries are also causing some marketers to submit pages that don’t belong to them to the engines. Here’s an overview of some of the key issues surrounding link origination and some advice for making the most of your linking pursuits.

A search engine indexes your web site (or anyone else’s) only to a certain depth and then moves on to the next site. The depth a search engine crawler will travel varies from engine to engine and even varies for the same engine from day to day and URL to URL. However, most crawlers go no deeper than three directory levels into any given site (yoursite.com/level1/level2/level3/).

You might find instances where a crawler has gone deeper, or shallower, but, in general, the key point is this: If links to your site originate beyond the third directory level of the originating site, the crawlers will never know those links exist. The link is deeper than the crawler is able to crawl.

Not to mix metaphors, but imagine fishing on a lake that’s 100 feet deep with a net that can be lowered only to a depth of 50 feet, and you get the picture. Anything that’s deeper than 50 feet is not going to be caught by the net.

This does not mean that such links are worthless. It means only that such links cannot be factored by the engines into the engines’ link popularity measurement. They can’t factor what they don’t know exists.

This raises an intriguing scenario:

Two sites offer nearly identical content.

Site A has 500 sites linking to it, but all 500 sites placed those links beyond their third directory level.

Site B has 25 sites linking to it, all of them at the highest (top) level directory.

Which site, A or B, is better positioned from a linking standpoint?

Surprisingly, you can’t say without knowing more about the links themselves. What kinds of sites do they exist on? Those 500 links to your site will be useless if they originate on random link lists with no context and no page views, or if all those links were beyond the third directory level on the originating site. Likewise, site B with only 25 links may be getting nice new traffic if all 25 links originated close to the surface (top level) of well-trafficked, topically relevant sites.

This is an extreme scenario. It’s more likely that your site falls somewhere in between. You have some good links, and you have some useless ones. You usually can’t control where the originating site places its link to your site. If I have a links page that is four directories deep on my site, then even if it’s the most useful links page in the world, none of the search engines are going to find it.

And this last fact has led to some unfortunate behavior by web marketers. Finding a link to their site and hoping to influence the search engines, they submit via the Add URL feature on any pages they come across that have a link to their site.

With all the search engines placing limits on the number of URLs they allow to be submitted per site per day, how do you like the idea that someone might be submitting your site’s URLs to the search engines without your knowledge? Pretty scary, huh? But it’s happening right now to someone somewhere.

Let’s sum all this up in a list of key points.

• If your goal is to improve link popularity for searchers, the links to your site need to originate as close to the top level on the originating site as possible.
• A link originating beyond the third or fourth level is still important if the originating site is topically relevant and useful. Yahoo is a good example. Most sites linked by Yahoo originate far beyond Yahoo’s third directory level. My own Yahoo listing is five levels deep, yet sends me hundreds of visits every day.
• Fewer purposeful links are better than nonrelevant laundry-list link lists or Free for All Links Pages (FFALP).
• It is never appropriate to submit another site’s URLs to the search engines unless you have received permission to do so.

Stay tuned for answers to reader questions and the importance of getting links in email-based publications next time.