One of the most passionate arguments I took part in was whether or not Taylor Swift was a good dancer.
The first thing you need to know about me is that Taylor Swift is my favorite artist. So you would have a hard time convincing me that she is bad in anything (because she is not).
SEO experts are probably the same way when they wonder if subdomains or subdirectories are better for SEO. As a marketer, this debate can cause confusion and analysis paralysis.
In this article, you will learn the differences between a subdomain and a subdirectory and how they affect SEO. There are pros and cons in both cases, and you will need to consider all of these factors before going ahead with your website project.
What is a subdirectory?
A subdirectory is a type of website hierarchy under a root domain that uses folders to organize website content. A subdirectory is the same as a subfolder and the names can be used interchangeably.
In a URL, the subdirectory comes after the root directory or the domain name. For example, HubSpot’s root domain is hubspot.com. So a subdirectory URL can be hubspot.com/pricing. Or it could be something more complicated like hubspot.com/pricing/sales. Below is an illustration of a possible subdirectory structure.
When it comes to subdirectories, think about a structure similar to nesting dolls. Each file can build on each other almost indefinitely. This means you can have a subfolder in a subfolder inside a subfolder until you have dozens or even hundreds of layers deep.
But just because you can, doesn’t mean you should.
Too many layers of subfolders can become an SEO nightmare. The URL chain becomes long and confusing, the user experience is threatened with every click it takes to access the next content, and search engine bots will find it nearly impossible to crawl your site for new content and new content. other SEO gains you might have added.
On the flip side, subfolders can be great for SEO as they keep all earned backlinks, domain authority, and page authority tightly tied to the root domain. And when the site is easy enough to navigate, the URLs are short and straightforward, like hubspot.com/careers, which means you can market specific webpages or landing pages by their URLs without confusing your audience.
What is a subdomain?
A subdomain is also a type of website hierarchy under a root directory, but instead of using folders to organize website content, it sort of gets its own website. This subdomain is always closely associated with the root directory, but it will usually have a separate content management system, template, analysis tools, etc.
The structure of a subdomain is quite flat at higher levels. You will have your root directory, then all the subdomains below in a horizontal row. All subdomains are at the same level. You won’t have a subdomain within a subdomain like you would with a subfolder within a subfolder.
SEO and subdomains
A subdomain can be great for SEO, but it will require a dedicated person or team who can manage it. Unlike subdirectories, the domain authority of a subdomain will not automatically revert to the primary domain name. You can also pay extra for tools or subscriptions if you’re billed by domain name, as each subdomain usually counts as a separate website. With these challenges in mind, let’s take a closer look at the benefits of using a subdomain.
Why use subdomains?
Subdomains are ideal if your business hosts a lot of content that would be difficult to manage on a single website. You may also find this structure beneficial if you are running multiple large, recurring campaigns that require separate landing pages or if you are considering partnering with another organization and want to split the project brand.
In short, subdomains make sense if you have a relevant business need to separate your website content.
When to use subdomains
- Different regions
- E-commerce store
There are a number of cases where a business needs to use a subdomain. Below are the most common.
Sometimes it doesn’t make sense to have your customer support on your main site. For example, Google uses support.google.com instead of google.com/support. The main reason is probably because of the structure of the site. Google FR is a search engine and the Google helpline is not part of its Search business line. Therefore, it needs its own subdomain to log in and properly serve its users.
2. Different regions
If you are serving multiple regions, either nationally or internationally, using a subdomain would be a good idea. If you had a site in German and one in English, it wouldn’t make sense to list them as subdirectories. For example, Craigslist uses subdomains for the different regions it serves. Here are two of its subdomain sites: orangecounty.craigslist.org/ or stgeorge.craigslist.org/.
Many businesses choose to have their blog as a subdomain. In fact, that’s what HubSpot does. If you notice it, the page you are on right now is a blog.hubspot.com page. However, this specific article is located in the Marketing subdirectory of the blog.hubspot.com subdomain. Sites can choose to have their blog as a subdomain if they have a content campaign big enough in mind to deserve its own hierarchy and growth path (more on this in a minute). Additionally, a subdomain is useful for a blog if you want to build a niche authority.
4. E-commerce store
For businesses that sell merchandise, in addition to their regular product or service, they can place their e-commerce store on a subdomain. HubSpot does this as well. In addition to our main software hubs, HubSpot products are available at shop.hubspot.com.
If your business is hosting events, it may be a good idea to partition this section of your site into a subdomain. Again, this is useful when you want to distinguish a section of your site from your regular product or service. Microsoft does it with its events.microsoft.com.
Subdomain vs subdirectory
A subdomain compartments your website so that you can establish specific types of content separate from your root domain. On the other hand, a subdirectory is a path within your site. Subdirectories are one level in the domain hierarchy. Subdirectories start from the subdomain to which they belong.
Technically, a website can use both a subdomain and a subdirectory structure. Subdomains usually contain at least a few subfolders to organize content, but probably not as many as a subdirectory. This is because there is a smaller variety of content covered on a subdomain than a root domain with subfolders.
It is therefore important to understand what will be the main structure of your website. To decide that, let’s take a closer look at the impact of subdomains and subdirectories on SEO.
How do subdomains and subdirectories affect SEO?
Some SEO experts believe that Google’s crawlers might mistake a subdomain for an entirely different website from the main domain. However, others say its crawlers can recognize subdomains as extensions of parent domains.
According to Google, the site crawls, indexes and ranks subdomains and subdirectories in the same way.
In the video below, Google Webmaster Trends Analyst John Mueller says subdomains don’t usually hurt a site’s ranking. In fact, he says Google is smart enough to see your main domain and your subdomain as being linked to the same website.
Some SEO professionals argue that subdomains do not share the authority as they receive inbound links (or backlinks) with the root domain. The reverse can also be true; Because subdomains are considered separate entities from your root domain, they may not inherit the link authority that you already created for your website’s main content.
Also, if you optimize pages for the same keywords on your main site and subdomain, you might be competing with yourself.
On the flip side, other SEO experts argue that subdomains make your site easier to navigate. Ultimately, this leads to a better user experience, which could lead to better engagement rates, thus improving your SEO.
Subdomains can be beneficial if you have a large business and the subdomains serve a different purpose and essentially operate as a separate business.
Since these subdomains have very different purposes, it doesn’t matter that the sites don’t share the same authority as the backlinks because they probably don’t target the same keywords.
Another benefit, according to some SEO experts, is that subdomains can help build niche authority. For example, you might want your blog to be seen as a separate entity from your product or service.
Conversely, if your site doesn’t have extended verticals on your navigation, you might not need to use a subdomain because you want the most links to go to your main site. If you don’t have a compelling reason to use subdomains, then subdirectories work fine.
Which is better: subdirectory or subdomain?
While this topic can often be confusing, the decision ultimately depends on the needs of your website. Subdomains can provide organization and structure to your site if you have a lot of different but important content to share. Subdirectories can be useful for small websites that don’t have a wide variety of content. Whichever structure you choose, you’ll want to keep abreast of SEO best practices in order to achieve your website’s goals. The free guide below will help you improve your site with a free SEO audit toolkit.
Editor’s Note: This article was originally published in February 2020 and has been updated for completeness.