When setting up a website, a lot of thought is given to how it looks and feels. The UI and UX take the center stage, followed of course by content that is attention-grabbing.
Most website owners do not pay much attention to site architecture. They are happy to let the web developer decide about such technicalities.
But do you know that if your site has subdomains you can end up as an also-ran in the great Google SERP race? This issue is difficult to fix because it is baked into the DNA of the site.
To know what subdomains are and why they matter in SEO, read on.
What Are Subdomains?
Think of a website as a house. A subdirectory (Gallery, About Us etc) is a room in the house.
A subdomain is another house on the same plot of land. The URL is the address. Slight variation of the same address can bring visitors to the main building or annex building.
A subdomain is a part of the website that is separate from the main section.
The name of the subdomain always precedes the name of the domain.
Let’s understand with an example:
www.mywebsite.com is a URL
The .com extension is known as a top-level domain. It could also have been .org or .biz or any other top-level domain extension.
mywebsite is the domain name.
It has to be purchased from ICAAN (through subsidiaries known as registrars such as Google Domains).
If there is a part of the site hosted on blog.mywebsite.com, then it is on a subdomain of mywebsite.com.
You do not need to buy a subdomain if you already own a domain.
If you have paid for registering mywebsite.com then using blog.mywebsite.com, and shop.mywebsite.com will not cost extra.
However, you do have to buy separate hosting for each of these.
Why Are Subdomains Used?
Typically, subdomains are used where information needs to be in a silo. A subdomain is a wonderful way to keep everything on the same IP address but separate.
For example, a business whose website is www.mybusinesswebsite.com might have the following subdomains for different departments:
Notice how it is used.
Whereas the original business is a .com with a gallery, a press corner, and a store, the business is operated through a .net site of the same name (could be any extension).
This prevents hackers from gaining access to principal databases.
The mybusinesswebsite.net is split into at least four subdomains. Each is meant for a particular set of managers and experts.
Hence, if an audit clerk from an external accounting firm needs access to invoices from the third quarter of 2019, he has no way to access the database on research.
Only the C-suite officers (CEO, COO, and various VPs) have access to all parts of the site.
But that principle has gone for a toss, with many sites having a blog and e-store on different subdomains.
Why Do Modern Sites Opt for Subdomains?
A subdomain is often used for what can be done by a subdirectory.
blog.mywebsite.com performs the same function as mywebsite.com/blog
But if the blog is hosted as a subdirectory (basically a new page on the website) it has to follow the same site architecture. That might interfere with the plans of a site where the owner wants a fancy blog with a design UI and UX different from the main site.
For obvious reasons, e-stores need their own subdomain. They are quite different and cannot have an About Us page or a Gallery.
The Case Against Subdomains
If your business has subdomains for better administration, e.g. finance.mybusinesswebsite.net, or sales.mybusinesswebsite.net, it does not matter.
After all, you are not looking to have them crawled by Google.
But if the public aspect of a site has subdomains, there might be problems.
- A subdomain is a different site
A subdomain is seen by Google as a separate site with its own metrics.
If you host great content on blog.mywebsite.com and it receives 1200 backlinks spontaneously (not impossible since an infographic can go viral) that does nothing for the SERP of mywebsite.com.
According to Google’s John Mueller, every subdomain is crawled separately.
Google does not say much about how it ranks websites, but that nugget has unmistakable implications. Your blog is not going to push your e-store to the forefront automatically through link juice.
A subdirectory can save you this headache. The content you share would power the website and all its sections up the SERP ladder.
If your site is well known and already has great name recall, a subdomain might not face a problem if it does not benefit from link juice. But an e-store struggling to get 600 visitors a day and five conversions should avoid the complications of a subdomain.
You have to list them separately, submit a different sitemap and monitor two sets of data.
- A subdomain extends the URL length
One of the axioms of SEO and excellent website design is to have URLs that are easy to remember.
The key is to have a small and succinct SEO-friendly URL that can be remembered easily.
When the net has a million websites, it is a bad idea to have a subdomain that makes the URL longer than it needs to be.
Remember that the subdomain does not show up in your website navigation.
It is possible to locate www.mywebsite.com/blog from the menu but not blog.mywebsite.com.
Of course, you could redirect all traffic going to the subdirectory to the subdomain, but that needs time and the visitor might bounce away.
Adding a subdomain complicates life in every possible way.
- A subdomain causes duplicate content problem
Google’s algorithm is quite wise in its own way. It dislikes duplicate content and tends to penalize the site that shared the content later.
If you share a 1200-word blog post with superb SEO keyword research and reuse large parts of it later, Google knows that all of it belongs to the same website. After all, no one can accuse one of plagiarizing one’s own creation. Nothing is going to get marked as duplicate content.
But if the same happens across subdomains, there will be the issue of plagiarizing.
If you have a blog subdirectory and also a blog subdomain and a set of articles get published on both, Google will shift one or both down the search rankings. Hiring a SEO expert will help you make the right choices.
- A subdomain causes confusion
Not everyone on the web is tech-savvy. Most don’t understand much beyond typing in a site URL and clicking the back button.
You want the visitors to be able to find the page they are looking for quickly and without confusion.
A subdomain-based site structure might lead some visitors to wonder where your shopping site is if they are on a blog subdomain.
To avoid this issue make sure that every section has internal links to every other section.
Are subdomains a blessing or curse? The answer would depend on who you ask.
For sites that are international and have a footprint in many nations, it makes sense to have a US, UK, Europe, Asia based subdomain.
Most auto MNCs plan their website this way. It helps to list service centers and other details that are relevant to a geographical region.
If you do not have a pressing need to create a subdomain don’t opt for it.