If you’ve ever come across a web address like blog.example.com or shop.example.com, you’ve already seen a subdomain in action. But what is a subdomain, and why do website owners use them? In this guide, we’ll explore what a subdomain is, how they work, why you might use one, how they differ from subdirectories, what impact they have on SEO, and how to create and manage them effectively.
What is a Subdomain?
A subdomain is a prefix added to your main domain name that helps create a separate, distinct section of your site. It appears before the main domain in a web address and is separated by a dot. For example, in blog.example.com, the word blog is the subdomain, while example.com is the main domain.
Subdomains act like mini-sites under your main domain. They can run different designs, host unique content, or serve specific purposes, but they always remain tied to the root domain.
Why You Might Use a Subdomain
Subdomains are often used when a website needs a clearly separated section for a specific purpose. Common examples include:
- Separate content areas: Such as blog.example.com for articles or support.example.com for help resources.
- Different functions: Like store.example.com for an online shop, or app.example.com for a web application.
- Targeting different audiences: For instance, en.example.com for English-speaking visitors and fr.example.com for French.
- Testing environments: Staging.example.com for testing new features without affecting the live site.
By using subdomains, you can keep each section organised while maintaining a connection to your main domain. This makes it easier to manage complex sites or deliver tailored experiences to different users.
Subdomain vs Subdirectory – What’s the Difference?
Although they can appear similar, subdomains and subdirectories work differently in terms of site structure and organisation.
- Subdomain: Appears before the main domain. For example, shop.example.com.
- Subdirectory: Appears after the main domain as part of the URL path. For example, example.com/shop/.
From a technical perspective, a subdomain is treated as a separate site in the DNS system, while a subdirectory is simply a folder within your main site. This means a subdomain can have a different hosting setup or even be managed by a different team, whereas a subdirectory will always share the same hosting environment and CMS as the main domain.
How Subdomains Impact SEO
The question of subdomain SEO is a common one, especially for businesses looking to maximise search visibility. Search engines generally treat a separate subdomain as an independent site from the root domain. This can be beneficial if you want to target different keywords, audiences, or regions without affecting the main site.
However, this separation also means that the reputation and visibility your main site has built (often referred to as Domain Authority) in search results will not automatically carry over to a new subdomain. Each subdomain is treated as its own website, so you’ll need to put effort into building it up separately with original content, links from other sites, and proper optimisation.
A subdomain can make sense when
- You want to serve a very different audience or region (for example, au.example.com for Australia and us.example.com for the United States).
- You’re running a distinct project or platform that is separate from your main brand (like blog.example.com or shop.example.com).
- You need a clear separation for technical reasons, such as hosting a forum or support portal.
A subdomain may not be the best choice if
- You’re simply adding more pages or categories to your existing site. In that case, a subdirectory (example.com/services) will usually perform better, as it builds on the authority of your main domain.
- You don’t have the time or resources to build out and maintain a full SEO strategy for each subdomain.
In general, if the content is closely related to your main site, stick with subdirectories. If it’s a standalone project or audience, a subdomain may be the right option.
How to Create a Subdomain
The exact process for creating a subdomain varies depending on your web hosting provider or platform. Some control panels make it a one-click option, while others require you to add DNS records and configure hosting settings manually. To keep things simple, let’s focus on the two main pieces of the puzzle that apply in most cases:
- Pointing the subdomain in your DNS Settings: You’ll need to add a DNS record for the subdomain (for example, blog.yourdomain.com) that directs it to the server where your website files are stored. Without this, visitors won’t be able to find your subdomain online.
- Configuring your hosting service: Once the DNS points correctly, your hosting service needs to know what to do with the subdomain. This usually means creating a subdomain entry in your hosting account and linking it to the folder or site files you want to display.
Both parts are essential. Think of it like setting up a new room in your house and also putting a signpost on the street so visitors know how to find it.
For specific steps, you should refer to support articles or documentation provided by the web hosting provider or platform you’re using.
How to set up a sub-domain with VentraIP
If you’re using VentraIP to host your website, you can easily set up a subdomain by following the steps provided in these step-by-step guides:
- Creating a sub-domain in cPanel: Perfect if you’re managing your site with our cPanel web hosting.
- Adding a subdomain to Free DNS Hosting: Ideal if you’re using our Free DNS Hosting system.
Choosing the right guide depends on your setup. If you’re unsure which one applies, feel free to contact our friendly Australian-based support team so they can point you in the right direction.
Understanding DNS Records for Subdomains
When you create a subdomain, your DNS settings decide where visitors are sent when they type that subdomain into their browser. Think of DNS (Domain Name System) as the internet’s phone book: instead of remembering long numbers, people use names like blog.example.com, and DNS translates that into the correct server address (often referred to as an IP Address).
Basically, it works a bit like this:
Phone Book: My Example Business → 03 9999 9999
DNS: shop.example.com → 192.0.2.123
There are two main record types you’ll usually see when setting up a subdomain:
| Record Type | What It Does | When It’s Used | Example |
|---|---|---|---|
| A Record | Points a subdomain directly to an IP address (a string of numbers that identifies a specific server). | Use this when your subdomain is hosted on a different server from your main domain. | shop.example.com → 192.0.2.123 |
| CNAME Record | Maps a subdomain to another domain name, which then resolves to an IP address. | Use this when your subdomain shares the same hosting as your main site or when pointing to a third-party service. | blog.example.com → example.com →192.0.2.123 |
IP addresses are the underlying numbers that represent your hosting server on the internet. An A record links your subdomain straight to that number. A CNAME record acts more like a shortcut, telling traffic “go wherever this other domain is going”.
Most hosting systems will set this up for you automatically, but it’s worth knowing how it works so you can troubleshoot if needed. Keeping your DNS records accurate ensures visitors always reach the right site quickly and reliably.
More on this: What is DNS? A Simple Guide for Everyone
Bringing it all together
Subdomains can be powerful tools for structuring your site, targeting specific audiences, and organising different parts of your online presence. By understanding what a subdomain is, how it works, and how it fits into your online presence, you can make an informed decision about whether it’s right for you.
If you’re ready to set up a subdomain or need fast, reliable hosting for your main domain and all its subdomains, VentraIP offers high-performance Australian web hosting to help your site run smoothly.
