Subdirectory vs Subdomain for SEO?

Should I Host my Forum in a Subdomain or Subdirectory?

The same question can be asked of a blog, directory, support, or any kind of affiliated site that has a relation to your main website. When it comes to a search engine's treatment of your content, do SEO's (Search Engine Optimizers in this case) prefer to put a related website such as a blog or forum in a subdirectory (example.com/subdirectory), or in a subdomain (example.com/subdomain)?

Remember to Cater to your User First

There's quite a few discussions around this topic circulating in the search engine forums of the Internet, and there's widely differing opinions. Which usually means there's no definite right or wrong answer. And which gives us at Guru of Search the opportunity to remind you not to over think things - not to spend so much time focusing on what a search engine might prefer, that you lose sight of your user's preferences.

Instead of thinking - will Google like this? Ask yourself - what is most practical for my users? Because in the end, search engines are constantly changing their algorithms. And they're changing them for the same reason you should not spend too much time on this decision - namely, they're tailoring their algorithms to best suit their main customer - the searcher.

Nevertheless, you'll notice that our forum is hosted in a subdomain. So you might ask how we arrived at the decision to host our forum at forum.guruofsearch.com, instead of guruofsearch.com/forum.

Subdirectory or Subdomain for SEO? Both are Okay

We ultimately made our decision based on technical factors. Namely, that given the two separate systems our websites run on (guruofsearch.com runs on Drupal, while our forums run on bbPress - an open source forum solution developed by the makers of the popular Wordpress blogging platform) - we needed to have the forum function out of a root directory, or subdomain, instead of a subfolder (subdirectory). It made the cooperation of the two CMS platforms more amiable, and helped us avoid a complex technical setup that would make it difficult, for example, to submit independent XML sitemaps for each system.

Subdomains are Treated more Independently

What it comes down to, as far as treatment from search engines is concerned, is that subdomains are treated more independently (ie. as their own entity) thatn subdirectories. We need to point out, however, that they are treated less independently than they used to be, as the algorithms have been updated to address the relevant connection between a main website and its subdomain.

Our Take - Deciding on Subdirectory or Subdomain

Technical merits aside, we probably would still have decided on a subdomain for our forum website. Why? Because it allows us to treat the website as a separate entity. Tests show that search engines take this same approach - a subfolder entity is treated as slightly more connected to the main website than is a subdomain. This makes sense given the way URL's are structured, if you think about it. example.com/forum is basically example.com/directory.

But for us, to the user this could be confusing - as we tend to associate directories with categories - ie. example.com/category. By placing our forum in a subdomain - ie. forum.example.com, we make it clear that the forum is its own entity, not a separate category or folder, but still maintaining a close connection to our main website.

The bottom line is that either decision will work for you. You should spend less time on this decision and more on generating and creating unique and meaningful content. And always place yourself in your visitor's shoes and ask yourself what they might think. Don't let your mind be sidetracked by what you think the search engines might be thinking. In the end, they'll change their minds, and you'll end up on a never-ending goose chase for a perfect solution that simply doesn't exist.