Knowledge Base

What is a Subdomain?

A subdomain is a domain name that is part of your main domain name (e.g., example.com) and derived from it. Technically, it is a label added before the main domain name. For example, blog.example.com, shop.example.com, or support.example.com. Subdomains are used to organize and separate different sections or functions of your website. This can help improve both user experience and SEO performance. If you would like to learn more about Domain Services, you can visit our relevant page.

Important Point: Subdomains can function as completely separate websites or be an extension of the main website. This makes subdomains versatile and adaptable.

Why Should I Use a Subdomain? What are the Advantages of Using a Subdomain?

There are many advantages to using a subdomain. Here are some of them:

• Organization: Subdomains help you organize the content and functions of your website. For example, if you have an e-commerce site, you can showcase your products at shop.example.com and publish your blog posts at blog.example.com.
• SEO (Search Engine Optimization): Search engines like Google may evaluate subdomains separately from the main domain. This can help improve your ranking for specific keywords. However, this situation can have both advantages and disadvantages. Poorly managed subdomains can negatively affect your SEO performance.
• Test Environment: When developing new features or designs, you can test them on a subdomain before publishing them on your live website. This helps you prevent errors and protect the user experience.
• Target Audience Specific Content: You can create special content for different target audiences. For example, you can create subdomains like en.example.com for English-speaking users and de.example.com for German-speaking users.
• Mobile Optimization: You can improve the mobile user experience by creating a subdomain optimized for mobile devices (m.example.com).

Real-Life Example: A university website may use subdomains for different faculties. For example, engineering.university.edu for the engineering faculty and medicine.university.edu for the medical faculty.

How to Create a Subdomain? Step-by-Step Instructions

Creating a subdomain is usually done through your hosting provider's control panel. Here is a general process:

1. Log in to the Hosting Control Panel: Log in to your hosting account. Usually, a control panel like cPanel, Plesk, or similar is used.
2. Go to the Domains Section: Find a section like "Domains", "Subdomains", or similar in the control panel.
3. Select the Subdomain Creation Option: There will be an option like "Create New Subdomain", "Add Subdomain".
4. Enter the Subdomain Name: Enter the subdomain name you want to create (e.g., blog).
5. Specify the Document Root: Specify the directory where the subdomain's files will be stored. This is usually a new folder under the public_html directory (e.g., public_html/blog).
6. Complete the Creation Process: After entering the necessary information, complete the creation process.
7. Check DNS Records: After the subdomain is created, make sure the DNS records are configured correctly. Your hosting provider usually does this automatically, but it's worth checking.

Important Note: The subdomain creation process may vary depending on your hosting provider. It may be helpful to review your hosting provider's documentation or contact their support team.

What is the Difference Between a Subdomain and a Subdirectory (Subfolder)?

The main difference between a subdomain (e.g., blog.example.com) and a subdirectory (e.g., example.com/blog) is the URL structure and how they are perceived by search engines. Subdomains are generally considered separate websites from the main domain by search engines, while subdirectories are considered part of the main domain.

Here is a comparison table:

Case Study: An e-commerce company, by setting up its blog as a subdomain (blog.example.com), aimed to focus on blog content without affecting the performance of the main e-commerce site (example.com). In this way, by implementing a separate SEO strategy for the blog, it managed to reach a wider audience.

How Do Subdomains Affect SEO?

The impact of subdomains on SEO can be complex. In theory, since subdomains are evaluated separately from the main domain, a separate SEO strategy can be applied to each subdomain. This can help improve your ranking for specific keywords. However, there are some disadvantages to this:

• Content Duplication: If the content on the subdomains is very similar to the content on your main website, search engines may perceive this as content duplication and negatively affect your SEO performance.
• Link Juice Dilution: Links to subdomains may not be as valuable as links to your main domain. This can lead to "link juice" being diluted and overall SEO performance decreasing.
• Management Difficulty: Managing multiple subdomains can be more complex than managing a single website. Separate SEO strategies, content calendars, and analyses are required for each subdomain.

Important Point: It is important to be careful and develop a good strategy when using subdomains for SEO. It is important to avoid content duplication, create unique and valuable content for each subdomain, and establish a good internal linking structure between subdomains.

How to Redirect a Subdomain?

Subdomain redirection means redirecting a subdomain to another URL (another subdomain, the main domain, or a different website). This can be used to automatically redirect users to the correct page and improve SEO. Here are some methods for subdomain redirection:

• .htaccess File (Apache Servers): On Apache servers, you can use the .htaccess file to redirect a subdomain. Here is an example:

  
  RewriteEngine On
  RewriteCond %{HTTP_HOST} ^subdomain\.example\.com$ [NC]
  RewriteRule ^(.*)$ https://www.example.com/$1 [R=301,L]
          

  This code redirects all requests to subdomain.example.com to https://www.example.com with a 301 (permanent) redirect.

• Hosting Control Panel: Most hosting control panels (cPanel, Plesk, etc.) offer a user-friendly interface for subdomain redirection. You can easily redirect using the "Redirects" or "Domain Redirects" section in your control panel.
• DNS Records: Subdomain redirection can also be done through DNS records. This method is generally more complex and requires technical knowledge.

Step-by-Step Instructions (cPanel):

1. Log in to cPanel.
2. In the "Domains" section, click "Redirects".
3. Select "Permanent (301)" or "Temporary (302)" as the "Type".
4. Select the subdomain you want to redirect.
5. Enter the redirect URL.
6. Click the "Add" button.

How to Ensure Subdomain Security?

Subdomain security is as important as the security of the main domain. Here are some tips to ensure the security of subdomains:

• Use SSL Certificates: Use SSL certificates for your subdomains as well. This encrypts the communication between your subdomains and users, ensuring data security.
• Use Strong Passwords: Use strong and unique passwords for the accounts you use to manage your subdomains.
• Keep Software Up to Date: Keep all software (CMS, plugins, themes, etc.) you use on your subdomains up to date. Updates often close security vulnerabilities.
• Use Security Plugins: Use security plugins for the CMS you use on your subdomains (e.g., WordPress). These plugins can help detect malware, create firewalls, and take other security measures.
• Perform Regular Backups: Regularly back up your subdomains. This helps you recover your data in the event of a security breach.
• Remove Unnecessary Subdomains: Remove unused or unnecessary subdomains. This reduces your attack surface.

Important Point: Security is an ongoing process. Regularly check and update the security of your subdomains.

Example Use Cases for Subdomains

Subdomains can be used for various purposes. Here are some example use cases:

• Blog: blog.example.com
• E-commerce Store: shop.example.com or store.example.com
• Support Center: support.example.com or help.example.com
• Documentation: docs.example.com or documentation.example.com
• Forum: forum.example.com
• Mobile Site: m.example.com
• Test Environment: dev.example.com or test.example.com
• Different Language Options: en.example.com (English), de.example.com (German), fr.example.com (French)
• Product Promotion: product1.example.com, product2.example.com

Real-Life Example: A software company can use subdomains for its different products. For example, project.softwarecompany.com for a project management tool, crm.softwarecompany.com for a CRM system, etc.

Subdomain Statistics and Trends (2025)

Subdomain usage continues to play an important role in the organization of websites and SEO strategies. As of 2025, here are some statistics and trends regarding subdomain usage:

Important Point: Subdomain usage may vary depending on the needs and goals of your website. It is important to conduct a careful analysis and seek support from SEO experts to determine the best strategy.