What Is a Subdomain and How Does It Impact SEO

What Is a Subdomain and How Does It Impact SEO

Amid all the “How-To” and “Best practices” out there, a lot of people are confused as to what affects their SEO. In this article, we will get to the nitty-gritty of what a subdomain is and how it can impact SEO.

Before we talk about what a subdomain is, let’s talk about what a domain is.

“A domain is the address of your website.” It’s what is typed into the URL bar to view a specific website on the internet. A variety of letters, numbers, and symbols can come together to make one. They can be used to identify a business or an individual. Domains are identified by their top-level domain (TLD) – the last part of the domain name that follows after the dot such as .com, .net, and .org.

But sometimes, a single domain isn’t enough for our needs. Sometimes we need more than one website for our business, which brings us to subdomains.

What Is a Subdomain?

A subdomain is a division of your website that you set up as a distinct “subsection” of your site. It can be formatted as, where your website’s domain name is substituted for “” For example, if the Huffington Post had a forum on their site, they might format it as

Let’s compare it with another (this time fictitious) example:

You can see there is no subdomain since “blog” is part of the root domain “”

Why Use Subdomains?

There are some instances in which a subdomain can be helpful:

Separating Content and Services from the Main Website

Subdomains are most commonly used when a company has several services or areas of focus. In these cases, the subdomains allow them to group related content and distinguish it from the rest of the website.

For instance, if you have an e-commerce site with a blog at and your main site is, it creates cohesion between the two parts of your business and makes it easier to disseminate information about both parts of your business without having to maintain two separate URLs.

To enhance accessibility and usability of a site

They can help you to organize your website into categories, which makes it easier for users to navigate and find what they’re looking for. For example, if you have an e-commerce business selling various kinds of products, you might create a subdomain for each category of product.

Creating a Test Version or Prototype of a Website

You can create a subdomain for a new site on your main domain to test it out before you make it live on the primary domain. This allows you to see what the site looks like and how it functions before you make any major changes without the risk of losing traffic or damaging key website metrics.

To Meet Location or Language-Specific Needs

You might also use subdomains when you have multiple locations or languages you’re catering to with your website. For example, if your business is located in the USA and Mexico and provides for the needs of English and Spanish speakers, then you could have an and respectively so that users can easily switch between languages.

When Creating a Mobile-Specific Website

Rather than embark on a major revamp of an already established desktop site, many businesses use subdomains to create a mobile-optimized version of their site instead. For example, Facebook uses as its mobile search destination.

Does the Use of a Subdomain Affect SEO?

The definition of how subdomains relate to SEO is unclear and evolving, but we’re here to give you some insight into what we know so far about their impact on your site’s search performance and how you can use them to enhance your site’s SEO strategy.

Google’s take on Subdomains and SEO

What people may not realize is that Google treats subdomains as a different entity that is independent of the main domain, explains Matt Cutt which means that any SEO efforts you put into one will not spill over to another.

As proof to support this claim, separate verification is needed for each subdomain as well as for the actual site content.

In a Webmasters video, Google’s John Mueller:

“You’ll need to verify subdomains separately in Search Console, make any changes to settings, and track overall performance per subdomain.”

To explain this concept further, let’s say that you have a main domain called and a blog on a subdomain named In this scenario, Google will treat your blog as an entirely separate entity – your blog will be a new website in its eyes.

How Subdomains can Impact SEO

Just a reminder: SEO is a potpourri of tactics and strategies that, when done right, will help your website get found by search engines and attract more visitors to your site. That sounds like a good thing, right? Well, it is. Here’s why subdomains can increase your search engine rankings:

The Keyword Connection

You may be thinking, “But I don’t have a keyword in my domain.” Well, there’s a solution for that. You can always create a subdomain with a keyword in its URL!

This is especially beneficial when your main domain is unrelated to the keyword and content you are trying to rank for in search engines (like if you are a dentist and want to rank for “web design company”). In this case, you could create the subdomain “” and voilà—you have created a keyword-rich URL.

A classic real-life example is New York Times (a major news website). They created a subdomain specifically for food so that they could still rank for keywords related to recipes despite having a broad website focused on general news topics.

A Positive user Experience is at the Core of Ranking a Website

Dwell time is a Google ranking factor of major importance (Search Engine Journal).

Yes, you read that correctly. Dwell time. The more time people spend on your site, the better. This is because search engines are using dwell time to assess a page’s quality, with a longer dwell time seen as a positive sign of relevance.

Circling back to user experience, let’s say your website without subdomains is a tangled mess of unrelated content categories. This can be slightly jarring for users and increase bounce rates because they’re overwhelmed and it doesn’t feel like they’re in the right place.

On the other hand, with the appropriate subdomains, everything would look cohesive and on-brand, making for a seamless user experience throughout all pages. The result would be more people staying on your website due to its easy-to-navigate structure and thematic organization, which will increase the dwell time and search engines will take note of that.

Builds your Authority in a Specific Niche

Say you’re an affiliate marketer and would want a seat on the first page for the keyword “dog food.” You have a website about pets already, but this website is about all types of pets – cats, dogs, birds, etc. You don’t have much content about dog food, so adding a “dogfood” or “caninediet” subdomain can help you build authority for that niche. It’s also going to be easier for you to rank for that niche topic.

Conclusion – are Subdomains Good for SEO?

The answer to whether subdomains are good for SEO is not simple. The answer is, it depends. Yes, there are situations where using a subdomain for your blog or other related content will be beneficial to the SEO of your site and allow you to gain more traffic and rankings in search engines. However, there are also plenty of examples where using a subdomain can be detrimental to your marketing efforts and help your competitors steal away market share from you.

If you’re considering using a subdomain for your  keep these points in Mind:

  • Subdomains can help contribute to improving ranking signals (or factors) such as dwell time and on-site experience. So there’s no harm going with a subdomain if it’s the only way you can easily achieve a great user experience on your site.
  • Subdomains can help target difficult keywords that hitherto are not in your website’s URL or niche market (keywords) not exactly related to your main domain. So again, there’s no harm in doing so.
  • Despite the positive SEO potential, a vulnerable subdomain is a sitting duck for potential cyber-attacks. This would not only cause downtime, hurt your brand’s bottom line and your website’s SEO as well. So, it is strongly recommended to use tools like a subdomain finder to always uncover possible points of exploits of any domain.
About author

Carl Herman is an editor at DataFileHost enjoys writing about the latest Tech trends around the globe.