Sub Domain or Sub Directory?

There has always been a lot of talk around using subdomains or subdirectories when creating new pages on people’s websites. So before we step into the war between Sub Domains and Sub Directories, let’s get to know them first.

The Domain Name System (DNS) has a tree structure or hierarchy, with each node on the tree being a domain name. A subdomain is a domain that is part of a larger domain; the only domain that is not also a sub-domain is the root domain. These sub domains help largely in organizing your website and making on-site navigation much easier. For instance, in www.wordpress.com, .com is the top level domain whereas wordpress in the second level domain. When you create an account and maintain a blog at the website, it gives you a ‘sub domain’ to the website commonly known as ‘Username’. Hence, yourwebsite.wordpress.com is a complete web address consisting of a top level domain, second level domain as well as ‘yourwebsite’ as the ‘sub domain’. Since your blog can be of all and any subjects, it becomes easier for a user to find you based on how you name your sub domain. If we’re clear with Sub Domain, let’s see what ‘Sub Directories’ are all about.

Subdirectories may refer to folders located directly within a folder, as well as folders that are stored in other folders within a folder. For example, the main directory of a file system is the root directory. Therefore, all other folders are subdirectories of the root folder. While hosting web pages or images etc. on the internet, Sub Directories largely help in creating sub folders under domains to host content. Hence, sub directories are useful for novice web enthusiasts who aim to keep things simple for themselves. For example, www.ilovepromocodes.com is a web address. And, www.ilovepromocodes.com/about/ is a web address along with ‘about’ as a subdirectory which can be used to host any content in terms of pictures, text, media files etc.

Now, Sub domains or Sub directories is the question!
A decision to use either subdomains or subdirectories may arise you/your company is looking to implement and integrate a blog to their site. You would be in a dilemma over blog.yourdomain.com or yourdomain.com/blog. Both are very different and treated very different.
Blog placed in Subdomain:

Advantages:

• Typically shorter URL than subdirectory
• Can pass some link value back to the root domain through cross-linking within template and articles.
• Can achieve a higher level of SERP saturation as search engines can rank more than the traditional 2 listings per site – multiple pages from your root domain as well as your subdomain.

Disadvantages:

• Subdomains DO NOT always inherit any or all of the positive metrics and ranking ability of their root domain (i.e. link equity, ranking equity, age benefits, etc).
• Some subdomains get zero benefit from the root domain they are on (ex: sites like WordPress.com where anyone can create their own subdomain and begin blogging).
• If you get inbound links to the subdirectory of the blog, it will build equity for the subdirectory. However, since it is technically a different site, it will not inherently pass that juice back to the root domain.
• More difficult to create and manage from a server perspective.

Blog placed in Subdirectory:
Advantages:

• Subdirectories tend to inherent some of the ranking benefits of the root domain.
• Inbound links coming into the blog subdirectory and/or its blog posts can build more ranking value, page authority, and link juice for the root domain.
• Utilizing the blog as a subdirectory, you can use blog posts to better enhance the root domain’s authority (and ranking ability) for a given topic by building hubs of content around that topic and cross-linking to key pages on the root.
• Any social sharing equity is passed back to root domain.
• Easier to organize content within the blog
• Easier to create and manage from a server perspective.

Disadvantages:

• Typically longer URL than subdomains
• Authority and link equity may diminish as your get deeper into a subdirectory structure – farther away from the root (ex: yourdomain.com/blog/seo/google)
• Won’t have the ability to achieve as high a level of SERP saturation as you would with subdomains.

If you’ve just skimmed this article
If you’re just skimming this article and want a summary, please refer to the info-graphic below. In the end, what matters is your proficiency and understanding of the web and how you use it to keep it comfortable. I would suggest you to opt for sub directories if you’re a novice in the field and after much trials and experimentation, you can move forward towards maintaining Sub Domains. However, I would also like to point out that sub domains are usually hosted by large companies or blogs for users who portray significant individuality in their products. For example WordPress and Google use sub domains for independent blogs and products respectively. However, if you’re simply aiming to branch out your website, maintaining sub directories is a smart choice!

Inputs: Jacob Stoops and Scott Design.