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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.
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.
