What are subdomains? How subdomain affects SEO

Share this post!

What are subdomains? And to understand the role of Subdomains on the Internet is not simple. Even for those who are tech-savvy. Today's article will reveal what you need to know about what a subdomain is as well as some knowledge about Root Domain. After this article you will be able to:

Get all the free knowledge about Subdomains (or 3rd, 4th level domains)
Know the purpose of use and how to create a Subdomain.
What are the difficulties to note when operating Subdomain?
How do subdomains affect website rankings on search engines?
First, let's find out what the concept of the Subdomain is…

What are subdomains?

Subdomains vs. Subfolders: Expert Cases What Is Better for SEO - SEOquake

The subdomain is an extension separated from the main domain. Subdomains are responsible for organizing and building content to serve a specific function (eg blog, forum, store, …) or another field of activity on the same domain root.

To make it easier to imagine what a Subdomain is, a Subdomain is simply a small part of the Internet hierarchy.

When you want to access any page on the web, whether it's your Facebook profile or a hot article on any website. We have to remember a sequence of random numbers, say Thanks to DNS, we don't have to remember such numbers.

Every system wants to work, especially one in which many people create new online landing pages every day. Then we need a set of naming rules for these pages to make it easier to identify the address. We need a hierarchy.

When you register a domain name, you can create unlimited subdomains at the domain name administrator. Some have even turned this into a business. They make money by buying good domains and then “selling” domain name registrations of subdomains.

WordPress.com, Squarespace, and several other platforms also do the same. They create separate profiles for users – on different subdomains – while the Root Domain is the same.

DNS Hierarchy

DNS itself is a hierarchy. Talking about the components that make up the operation of a website's domain name (such as domain.me) you have to go from right to left.

Starting from the top-level domain, it's called the Top Level Domain (TLD), like .COM, .BIKE, .ME. Take blog.yourwebsite.me as an example, then .ME is the top level domain name or the domain level 1, yourwebsite.me is the 2nd level domain and blog.yourwebsite.me is the 3rd level domain.

Sometimes people think that a subdomain is a 3rd level domain. In the above example, the blog is the subdomain of “yourwebsite.me”. At this point, “yourwebsite.me” is the Root Domain or “blog”. There are many ways to express the composition of domain names and sometimes they also mean the same thing.

After understanding the concept of exactly what a subdomain is, let's find out how subdomains are used?

What is the purpose of the Subdomain?
Even though the subdomain is part of the main website, search engines still see the subdomain as an independent entity. People realize that and decide to use Subdomains for many other purposes. Even when they don't want a certain part of the website to be indexed by Google compared to the rest. Subdomains are commonly used to:

Create a separate website for certain users

This is especially true if you want to focus on serving other areas, the content and language of your website must therefore vary from area to area. Sometimes creating multiple different websites is much easier than maintaining one that works in multiple languages.

Craigslist is a site with many separate subdomains for each different region. In addition to adjusting the content accordingly. They also use Subdomains to optimize websites separately for each territory. For example, when I go to the Craigslist website, the page takes me to https://zagreb.craigslist.org/ corresponding to my current location.

Many people do not notice that “www” is the subdomain of the domain. Actually you can replace “www” with another subdomain, as in “so.awesome.me” or remove the subdomain and keep just “aweso.me”.

Separate your blog or e-commerce site from your main website

You may want to do so due to different blog sizes (possibly increasing), and the difference between blog designs. Different CMS or blogs are used for different purposes than the main domain. For example, because Airbnb's main website is for booking tickets, the company has to separate the blog section in its own domain, blog.airbnb.com.

Save costs when taking advantage of Subdomains

When using a Subdomain, you don't have to pay anything when you have registered a domain name, so you don't have to spend extra money to buy a new domain and can still create many other websites as a Subdomain. Moreover, you can take advantage of the interface design on the main domain site without having to pay additional website design costs.

Create a mobile-specific site

You can create Subdomains to provide the best experience for users who use mobile devices. Instead of building highly responsive websites that require a lot of things to accommodate different screen sizes.

You can choose to be more flexible than providing a separate experience for each screen size. Instead of having to align the content to fit the size. Your website should be able to determine the device type and provide only the correct layout for that size.

For example, laptop users will go to yourwebsite.me while mobile and tablet users will go to m.yourwebsite.me which is managed on a Subdomain.

Subdomains should create a mobile-specific page

If you have multiple users creating profiles on Root Domain
When you create a profile on Tumblr, your page will be youprofile.tumblr.com. Many service sites have similar functions, you can choose to connect the domain name with the profile later.

The disadvantage of having many different Subdomains, especially if you want to sell or transfer them to others to use, is when the Subdomain and the Root Domain are considered as one, in many cases the Subdomain is “flagged” by the user for suspicion of a fake attack.

If you have 10 domains and only 1 of them is flagged. Then the Root Domain and the remaining 9 Subdomains will be the same.

One of the values ​​of “.ME” is to keep everyone safe. That's why we will block domains used to spread viruses, phishing attacks, and spam. However, we always have trouble when a Subdomain is flagged. Because the only way to make sure this site doesn't annoy users is to lock down the entire Root Domain.

This means if you have a Root Domain with many Subdomains from many other users. You have to keep track of what they do with those subdomains.

In case some users use the Subdomain to perform nefarious acts on the network, the whole domain will also be penalized. If that happens then you must remove the user and provide useful proof. Show that you did this to remove the penalty for the domain, but remember that prevention is better than cure.

Distinguish Domain and Subdomain

Tên miền, domain là gì? Mua ở Việt Nam hay nước ngoài? - Motnoi.com

Domain: The main domain name of a website on the Internet. To build a website, the first thing is to register a domain name and use a hosting service to develop a website.

Subdomain: This is a subdomain extending from the main domain, functions, and functions independently as a main domain.

Although Subdomain and Domain do not have much difference, it is not too difficult for users to recognize which is the Domain and which is the Subdomain. Note that the domain is only abc.com, www.abc.com is a subdomain. www is not an essential part of a domain name nor is it required, you can replace it with docs.abc.com,…

Based on the above concepts and examples, you can easily distinguish which is the domain, which is the subdomain when accessing different websites.

Endless Controversy: Sub-domain vs Subdirectory

A subdirectory, also known as Subfolder, is an extension of the Root Domain, used to organize content on a website. In the domain name “domain.me/blog”, “blog” is the subdirectory of domain.me.

This is a never-ending debate about which is better to use. When organizing your site: Subdomain or Subdirectory from an SEO perspective. Here are the pros and cons of both.


Subdomains are not only viewed by Google as an independent website but are also hosted on multiple separate hosting accounts. This means you have to pay hosting costs for each subdomain.

If so, then I would recommend looking for a registrar that offers promotional support for multiple hosting accounts. If you choose Subdirectory then you only pay one-time hosting fee. The amount depends on the size and speed of the website.

In the past, people preferred to use Subdomains. Because this way, you can fool the search engines by stuffing keywords you want to rank for in the Sub Domain. But nowadays this trick will be penalized by Google so it is best to focus on content.

This can be beneficial or harmful depending on your needs.

With Subdirectory, you can customize the page according to different regions, products, users, etc. If this is what you need, that's great and you have the resources to create quality content products for each Sub Domain and optimize according to SEO standards. This is how you optimize your website according to regional search results, similar to Craigslist.

With a subdirectory, you don't have many options to customize the content on your website. But it will be easier to manage the resources you have. Because you don't need to create a lot of content according to different requirements.

SEO Ranking

Level of influence on SEO rankings between Subdomain and Subfolder
From a Google perspective, using a Subdomain or a Subfolder doesn't seem to matter. Last year, John Mueller (Google) claimed that Google can figure out what you're trying to do. As long as you are not creating a large number of empty subdomains, it doesn't matter whether you use a subdomain or a subdirectory.

Back in 2012, Google representative Matt Cutts said the same thing when he said that for Google, a Subdomain or a Subdirectory is roughly the same, and Google considers both as a domain.

At first, Google provided different search results for each subdomain then See them as a completely independent websites from each other and from the main domain. The problem arose when people started using this loophole to compete for multiple subdomains for the same keyword.

From there, Google turned to try to find the link between the Subdomains and the Root Domain. If reasonable, Google will unify the results and only show a single domain on Search Result.

My SEO guide, MOZ, says:

Because search engines use a different metric system for domains than subdomains, webmasters should place link-worthy content such as blogs in a subfolder rather than a subdomain (e.g. www.example.com/blog/ instead of blog.example.com) Note except this is a website in a specific language (eg en.example.com for the English version of the website)

And it seems that this is also the view of many SEO experts.

I think the question between Subdomain or Subfolder can be solved on a case by case basis because which is better depends on what you need. And to rank high in search results, you need quality content that brings real value to users.

When to create a Subdomain?

Subdomain Là Gì? Subdomain Ảnh Hưởng Xấu Tới SEO Không

The question you always ask and need the correct answer, right? Here, I will give you the most accurate answer – You should use a Subdomain when:

The Enterprise launches a new product/service

The business has just launched a new product line for a customer group that is not the same as the customers of the main website. A subdomain is a tool that helps businesses in the ability to create a new campaign/experimental content.

After creating the page, you can advertise this campaign if it really works. At the same time, you can make a decision whether to continue building the website or delete this Subdomain.

This is a tool that helps you to quickly and cost-effectively test experimental content.

Manage and support the best websites

To increase the efficiency of the website in managing and arranging everything in a clear order – Subdomain will be the best choice for you. You just need to separate each product group into its own subdomain websites and assign administrators. Then, the management becomes easy and well-controlled. In particular, for e-commerce sites, the security is more thorough than blogs or review sites, only when separating them will the security be maximized.

Promotion and branding support

Creating a product launch website with the support of a Subdomain both helps businesses reach customers quickly and launch effective advertising campaigns. In addition, you can take advantage of traffic from the main domain which can make SEO more accurate. Only with the right strategies and the right campaigns can businesses build brands quickly and sustainably.

Instructions for creating Subdomains

After you have registered a standard domain name, in my guide to creating this Subdomain, you will do 2 steps as follows:

Think of the Subdomain you want to create

Activate and redirect the Subdomain to your new website (or third-party intermediary)

#1: Thinking of the a Subdomain name

Step 1 of how to create this Subdomain is very simple. What you need to do is think of a subdomain name that is short and relevant to the purpose of the page.

Usually, Subdomain can include characters from a-z, A-Z, 0-9, and hyphen (in case surrounded by other characters and numbers); no distance.

But this rule also varies by domain registrar so it's best to double-check your case. Or you can also use popular subdomains like shop, blog, language (en/vi), location (Philadelphia), forum, events, community, help, news, jobs.

#2: Activate, navigate the Subdomain to a new website

Step 2 of how to create this Subdomain is quite difficult because to do the whole process you not only need to activate the Subdomain but also have to determine the location of the page on the website. This location could be:

Part of your existing website
Websites or third-party URLs
Your brand new website
The exact steps in how to create this domain depend on the domain administrator and/or web host.

But one thing is for sure, if you only use one company for both domain name and hosting, things will be much simpler. Because you can set up everything with just one user Control Panel. Whereas if you use the domain and hosting from two different companies. You need to follow the content regulations and privacy policies of each party.

Manage Subdomains

To manage the Subdomain you go to the manager through the Control Panel of your hosting account. Select the Subdomain item from the Control Panel. Enter the Subdomain you want and press the “Create” button to execute.

After you have created a Subdomain, go to “List current Subdomains” to see a list of Subdomains you have created. From here you can easily manage the entire Subdomain.


Hopefully, the above content has provided all the free information and helped you find the most complete answers to these questions What is a subdomain? What are subdomains used for? And more importantly, you know how to create the fastest Subdomain.

Share this post!

Similar Posts