What Is A Subdomain? Everything You Need To Know (2024)

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A subdomains is a type of domain that is part of another domain. You can think of it as a separate branch from your main website. For example, if you’ve ever read a WordPress blog, you might have noticed that the domain (or URL) is the name of the blog + “.” + worddpress.com (i.e., blogname.wordpress.com). In this case, wordpress.com is the domain, and blogname.wordpress.com is the subdomain.

Subdomains can be used for a number of reasons, from prototyping sites to using two different themes. In this article, we’ll discuss what a subdomain is, when to use a subdomain, how subdomains influence search engine optimization (SEO) and how to set one up through your domain registrar or web host.

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Subdomain Definition

A subdomain is an extension or add-on to your business domain name. Subdomains are used to organize different functional parts of the website.

Say you have a domain name yoursite.com. You can have subdomains such as blog.yoursite.com or store.yoursite.com so that your store and blog can be designed, organized and optimized independently from your main website. As you continue adding different functions to your domain website, you can use new subdomains to separate them from the main website.

The URLs of domain names and subdomains are treated as separate entities—which brings us to the question of how a subdomain appears in the domain URL.

Structure of a Subdomain

The subdomain is appended before your domain name to create a new URL. Once this URL is created, it can have pages of its own as with any website.

What Is A Subdomain? Everything You Need To Know (3)

Characteristics and Parameters of a Subdomain

Here are some important things to know about a subdomain:

  • A domain can have up to 500 subdomains
  • You can create multiple levels of subdomains such as store.product.yoursite.com, test.forum.yoursite.com, etc.
  • Each subdomain can be up to 255 characters long, but for multi level subdomains, each level can only be 63 characters long

When to Use a Subdomain

Subdomains are used to:

  • Streamline site hierarchy
  • Improve user navigation
  • Create a prototype or test version of a website
  • To use two different themes with different functions for one domain (e.g., a blog, forum, e-commerce store, etc….)
  • Create location- or language-specific sites
  • To create a mobile-specific site

How To Create a Subdomain

The process of setting up a subdomain will vary slightly depending on where your subdomain is registered. However, generally the process to create a subdomain will look something like the following:

Here’s how to set up a subdomain:

  • Navigate to your domain name registrar or web host (e.g., Bluehost or DreamHost)
  • Select domains from your account dashboard
  • Find and select subdomains
  • Create your new subdomain

For more information, visit your domain registrar or web hosting provider’s help center for detailed instructions on how to create a subdomain. Additionally, your provider should be able to assist further via support should you have any issues along the way.

Subdomain vs Subdirectory

There is some confusion around subdomains vs subdirectories, and rightfully so. The two are seemingly very similar, yet each has a different structure, site organization and impact on SEO. A subdirectory uses folders under the primary domain name to organize content on your website. A key difference is that subdomains are treated as separate websites and do not inherit any domain authority of the parent website. Its SEO has to be built from scratch.

Subdomains vs subdirectories at a glance:

  • Subdomain: blog.yoursite.com
  • Subdirectory: yoursite.com/blog

Both subdirectories and subdomains have their own advantages and disadvantages, and ultimately it’s your decision what your website needs.

Frequently Asked Questions

Can subdomains affect website SEO?

A subdomain is treated as a separate website, so it doesn’t affect the SEO of your main website. It does not inherit the domain authority, page authority or ranking of the parent website.

What is a wildcard subdomain?

A subdomain that has a wildcard character asterisk (*) as the name of the subdomain is a wildcard subdomain. Creating a wildcard subdomain points all non-existing subdomains to a specific folder in your account. Typically, wildcard domains are made to point to the home page.

To create a wildcard subdomain, put an asterisk (*) in the subdomain field and you are ready to go

When should I use a subdomain?

Subdomains are most commonly used when you need to stage or prototype a site, add new functions to an existing website (and need to use two different themes to do so), create location- or device-specific websites or to improve the hierarchy of the website content.

How do I buy a domain name?

A domain registrar service will let you quickly search for available domains. Once you’ve chosen one that you like, the service will walk you through the checkout process and offer guidance on how to connect your domain to your site.

What Is A Subdomain? Everything You Need To Know (2024)


What is this subdomain? ›

A subdomain name is a piece of additional information added to the beginning of a website's domain name. It allows websites to separate and organize content for a specific function — such as a blog or an online store — from the rest of your website.

What is a subdomain name example? ›

While a subdomain will appear before your TLD, a subdirectory link will include the subdirectory name after the original TLD. For example: Subdomain example: mysubdomain.mywebsite.com. Subdirectory example: mywebsite.com/mysubdirectory.

What is a valid subdomain example? ›

An example of a subdomain is store.yourwebsite.com . Here, 'store' is the subdomain, 'yourwebsite' is the primary domain, and '.com' is the top level domain (TLD).

What are common subdomains? ›

These tend to be:
  • blog. [domain].com.
  • news. [domain].com.
  • landing. [domain].com.
  • articles. [domain].com.
  • resources. [domain].com.
  • insights. [domain].com.

Is A subdomain a URL? ›

Regular domains are your standard URLs like splashthat.com or splashthat. events. Subdomains are a unique URL that lives on your purchased domain as an extension in front of your regular domain like support.splashthat.com or blockparty.splashthat.com.

Why do I need a subdomain? ›

Subdomains are an excellent way to organize your website without damaging anything. A specific section of your website may be receiving increased engagement that needs special handling on a different platform.

How to choose a subdomain name? ›

Your subdomain name is not case sensitive, and cannot contain spaces or special characters (e.g. ! @#/). The shorter the subdomain name the easier it is to type for those visiting your websites, so don't try to add too many names or words in your subdomain name. Be aware of unfortunate naming accidents!

What should I put in a subdomain? ›

Add a subdomain
  1. Name: The hostname or prefix of the record, without the domain name such as blog or shop. The Name must follow these guidelines: ...
  2. Value: The IP address the record will point to. ...
  3. TTL (Time to Live): The amount of time the server should cache information before refreshing.

What is common name for subdomain? ›

If the certificate is issued for a subdomain, it should be the full subdomain. For instance, for the www and api subdomains of example.com , the common name will be www.example.com or api.example.com , and not example.com .

Can a subdomain be malicious? ›

Phishing: SubdoMailing attackers use compromised subdomains to send massive amounts of spam emails. These emails can appear legitimate, tricking recipients into clicking malicious links or opening attachments.

Does a subdomain need to be registered? ›

Rather than registering a new domain name, you can always create a subdomain using your existing domain name. A subdomain is an addon to your primary domain with its unique content. It is a separate part of your website that operates under the same primary domain name without you purchasing a new domain.

What are the rules for subdomains? ›

You can create multiple levels of subdomains such as store.product.yoursite.com, test.forum.yoursite.com, etc. Each subdomain can be up to 255 characters long, but for multi level subdomains, each level can only be 63 characters long.

What are the disadvantages of subdomains? ›

One of the disadvantages of choosing for a subdomain is that because search engines see them as separate sites, they're treated as separate domains when it comes to determining rankings. Considerations need to be made for developing a subdomain into its own entity.

What does a subdomain look like? ›

To recap, a subdomain is the portion of a URL that comes before the “main” domain name and the domain extension. For example, docs.themeisle.com . Subdomains can help you divide your website into logical parts or create separate sites, for example a separate blog for each sports team.

What is the best use of subdomains? ›

Typically, subdomains are used if there is content that is distinct from the rest of the site. For example, blog.examplesite.com and shop.examplesite.com are subdomains of www.examplesite.com.

How do I find a website subdomain? ›

By search engines

Search engines like Google supports various advanced search operators to refine search queries. These operators are often referred to as Google Dorks. We can use site: operator in Google search to find all the Subdomains that Google has found for a Domain. Lets take an example on “site:vulnweb.com”.

What is a subdomain in an email address? ›

An email subdomain delivers email from an address underneath the umbrella of your root domain. The subdomain is related to your root domain, but inbox and internet service providers (ISPs) treat it separately. You've likely seen subdomains used for websites.

What is Google subdomain example? ›

Create a subdomain in Google admin console

A subdomain makes the domain verification process easier. For example: If your primary domain is "tailspintoysco.com", your subdomain can be "gws.tailspintoysco.com".

What is subdomain phishing? ›

Termed “SubdoMailing” by Guardio, this series of attacks exploits the compromised subdomains of reputable companies to disseminate malicious emails. Investigations have revealed that this malicious campaign has been active since 2022.

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