In this article, you will learn what a subdomain is, how to create one, why you would want to do so, and what measures you need to take to protect a website with subdomains.
What are subdomains?
To answer this question, it is important to understand that each domain name consists of levels. They are separated from each other by dots. This structure allows the Domain Name System (DNS) to function correctly, which is the technology that enables browsers to find specific websites.
There can be up to 127 such levels. It is important to note that none of them can be longer than 63 characters. At the same time, the maximum length of a domain, including all subdomains, cannot exceed 255 characters. In addition, some registrars may impose additional, more stringent restrictions.
These levels are counted from right to left. From a technical point of view, hostpro.com is a .com subdomain, and blog.hostpro.com is a subdomain of hostpro.com. However, in practice, the first two levels are simply referred to as domain names. This is because they do not change throughout the entire registration period. But starting from the third level, these are subdomains that you can add at your discretion in unlimited quantities.
A subdomain is a part of a domain located to the left of the domain name. In other words, it is a third-level domain or higher, such as mail.google.com, blog.google.com, support.google.com.
Are subdomains different websites or the same one?
This question is often asked by those who want to structure their website. To do this, you can use subdomains (shop.google.com) or subdirectories (google.com/shop). Each of these options has its own advantages and disadvantages. While subdirectories are clearly part of the same website, subdomains are separate entities with unique domain names.
Search engines treat subdomains as separate websites. In other words, the authority of the main website and its backlinks do not affect subdomains and vice versa. This allows you to target a different audience and perform separate functions. We will discuss this further below.
Please note two additional considerations. First, subdomains must be verified separately from the main domain in Google Search Console. Second, if the content you want to place on a subdomain affects the SEO performance of your main site, you may want to create subdirectories (subfolders) instead of a subdomain. This will allow you to keep the content on your main site, just moving it slightly for better search logic and user convenience.
What are subdomains used for?
Subdomains provide the opportunity to obtain a unique name for a section or service on your website. The main reasons for this decision are:
Content organization. By using a subdomain, a company can highlight one of its services or projects. This is especially relevant if these services are aimed at different audiences or markets that are radically different from each other. For example, Google services are located on subdomains: drive.google.com, mail.google.com, etc.
Load balancing. A subdomain connects to hosting separately. This allows you to distribute the load between different servers. For example, subdomains can be used for internal company needs, such as a testing environment, image storage, a sub-site exclusively for employees, etc.
Working with clients. Your clients can create their own accounts or websites based on subdomains.
Testing. Before using a new CMS, you can run it on a subdomain to evaluate all its advantages and disadvantages.
New business direction. For example, if e-commerce is not your main service, but you want to open an online store at store.yourcompany.ua.
Regional/local segmentation. Let’s say you’ve decided to set up local branches of your company. In this case, you may need to publish separate information for users in each region. To do this, simply add the name of the city or country as a subdomain. Subdomains are also a common solution for creating multiple language versions of a website, for example, en.yourcompany.com, fr.yourcompany.com, ua.yourcompany.com.
Advantages of subdomains
Subdomains are great for organizing and separating parts of your website. If you have a large collection of resources, such as technical documents, a blog, a knowledge base, or a store, a subdomain allows you to gather everything in one place without cluttering the main architecture of the site.
This is important because search engines like well-organized sites. Google gets angry about structural disorder and punishes it by lowering the ranking. This is a common problem because all sites grow over time, with new pages being added here and there. By moving related pages to the appropriate subdomain, you can maintain the authority of your main domain and possibly even improve it.
Other advantages of using subdomains include:
- you only need to pay for the registration and renewal of one main domain ;
- pages are more relevant thanks to geo-dependent keywords if you use a subdomain specifically for localization;
- you can localize offers for several countries with the same language or for different regions of one country;
- additional linking of the main domain to subdomains is always a good idea.
Disadvantages of subdomains
A subdomain should be treated in the same way as a new domain when it comes to search engine optimization. This means that it will need its own SEO strategy, its own backlink base, and unique content that does not duplicate the content of the main domain.
Also, note that if a subdomain is needed for localization, then the main domain in national zones, such as .ua (for Ukraine) or .de (for Germany), will not be suitable in this case.
How to add a subdomain?
If you are a user of our virtual hosting , you can create a subdomain by following a few simple steps. First, go to the cPanel hosting control panel and find the “Domains” section.
Previously, subdomains were created in a separate section, but in newer versions of cPanel, they are created in the same place as domains. Therefore, you will need to click on the “Create New Domain” button.
After that, enter the name of the subdomain you want to create in the “Domain” field. It is also important to uncheck “Share document root” when creating subdomains. Specify the directory where files from this subdomain will be stored or leave the default setting. Then click the “Submit” button.
That’s it, your subdomain is created.
How to find out which subdomains a website has?
This information is usually needed by SEO specialists who perform technical analysis of websites, website owners, and marketers. For example, duplicate content may have been left on one of the subdomains, but everyone forgot about it. Or you may simply need information about the subdomains used by your competitors.
There are several ways to find information about the subdomains of a particular website.
Google search operator
Google will show you all indexed subdomains if you use a special operator. Just don’t forget to change google.com to the website you want to find information about.
site:google.com -inurl:https://google.com
Special services
You can also use free services such as:
- Subdomain Finder
- DNSdumpster (блок Host Records (A))
- Pentest Tools (розділ «Scans» ⇨ «Subdomain Finder»)
However, they do not always provide information about all subdomains. Therefore, if you require optimal results, consider utilizing the paid platform Serpstat. Here, you will be able to locate all subdomains of a specific domain.
How to protect a website with subdomains?
To protect a website with all its subdomains, you need to install an SSL certificate on the website. This is a special cryptographic protocol that guarantees a secure connection between the client and the server, as well as the confidentiality of data exchange between them.
With SSL certificates , any data, including personal information, geolocation, banking data, images, etc., is delivered to the recipient without interference from third parties.
If you are a website owner who cares about the security of your customers, then you definitely need to order an SSL certificate . What’s more, you can now order it for 2 or 3 years at once. It should also be noted that most popular browsers have a policy of simply not allowing users to access website content if SSL is not installed on it. The user will receive a full-screen message stating that the connection is unsecured.
An additional bonus is that Google’s algorithms, with other SEO indicators being equal, promote websites with paid SSL from trusted certification centers higher in search results.
If you have a website with subdomains, only specialized certificates such as Wildcard will suit you. They will encrypt both the main domain and all its subdomains at the same time. This is economical and convenient, because you no longer need to purchase, install, and then reissue SSL for each subdomain.
In conclusion
So, we can summarize: subdomains are third-level domains and above. They are usually used to structure information on a website, distribute the load on it, or allow users to create their own websites or accounts based on your domain.
To protect your website and all its subdomains, use Wildcard SSL certificates. This will increase trust in your resources among both users and search engines.