What Is a Subdomain? The Ultimate Guide to Definition, How It Is Used, and Good Examples

Confused about subdomains? It’s all about organising website content under a web address.

So, what is a subdomain, you ask? When you started your business, you set up a website where people could find out more. Now you’ve been trading for a while, you want to start selling your wares through the site, and write a blog with news and views from the industry.

You could just do this by adding new pages to your website, or you could buy separate domains for each new service. But there is another option—creating subdomains.

If you’re thinking, “Wait. That sounds a bit technical.  Exactly what is a subdomain and how does it work?” Well, don’t worry—our ultimate guide will tell you everything you need to know.

What Is a Subdomain? Definition In a Nutshell

Let’s answer the burning question: what is a subdomain name? It’s basically an extra piece of information you can add to your domain name. It takes the form of a prefix, which goes after the www but before your business name.

It means you can create separate sections of your website for different functions or purposes and easily direct visitors there. You may want to do this for an ecommerce store, a blog, or a customer forum. Subdomains operate as independent URLs, but they’re still part of your primary domain.

What Is the Difference Between a Domain and a Subdomain For a Website? Understanding the URL Parts

You may still be wondering exactly how a subdomain differs from a domain and how the various parts of a URL fit together. The whole URL (uniform resource locator, in case it ever comes up in a pub quiz) is the address of a web page.

What is a domain? It’s the segment of a URL that identifies your website, and the name is divided into two parts. The unique identifier, often the business or brand name, is called the second-level domain (SLD). It’s followed by an extension like .com or .uk, called the top-level domain (TLD).

So, what is a subdomain in a URL? This is the bit that appears before the SLD. The most common subdomain is www, but you can use words like “blog” or “shop.” For example, the main OnlyDomains web address is onlydomains.com. But the customer support section is set up as a subdomain: support.onlydomains.com

And we can’t forget the other parts of a URL. There’s a protocol at the start (http:// or https://), and there may be a page path at the end (such as onlydomains.com/about-us/contact-us).

But What Is a Subdomain Used For? In Simple Terms

The main reason for using subdomains is to create separate areas for diverse content and services, making it easier for visitors to find what they need. Examples are blogs, online stores, and subscriber-only content.

You’re basically creating a website within a website, keeping everything in one place for clarity and efficiency. Users already know your primary domain, so they should automatically trust the subdomain. It might be harder to get them on board with a whole new domain.

You can also use subdomains to ease the traffic load to your main site, to test new pages or features, or to track individual marketing campaigns. You might want to create a mobile-optimised version of the site, such as mobile.mysite.com

Do I really need subdomains for my website?

So, it all depends on what you want to achieve and on what your business does. There’s no point setting up a subdomain for just a few pages, but it works well if there’s enough content for a new section. It also makes sense to separate something like ecommerce, which needs a more complex setup for handling transactions.

If you plan to launch a new product type, a subdomain is a good idea. But, if you’re doing something completely different, you may be better off creating a business website specifically for the new offering.

If you’re expanding into new regions, you can use subdomains to create content that’s localised or in another language. This helps you to rank for different keywords, as subdomains appear in search results independently of the main website. Subdomains can also improve security, as a hacker might access one subdomain but not the whole website.

How many subdomains can I have with my domain?

This really depends on the pricing plan you arranged with your domain registrar or web hosting provider. Once you’ve bought a domain name, some registrars let you add unlimited subdomains, while others limit the number or impose an extra fee.

Ok, So What Is a Subdomain Example? Let Us Show You

Here are a few examples of how you can use subdomains for your website and how they appear to users.

• Separating functions: Google uses subdomains for its different functions, like Google Docs (docs.google.com) and Google Ads (ads.google.com), while Amazon does the same for its music streaming service (music.amazon.com)
• Localisation: You can use subdomains for each branch of a business, such as a garage franchise. General information would appear on www.mygarage.org, while a list of services specific to your Cambridge branch would be at cambridge.mygarage.com
• Languages: You can use subdomains to show which language the content is written in as Wikipedia does. So, en.wikipedia.com shows it’s in English, while de.wikipedia.com denotes German.
• Countries: If you want to reach audiences in different countries, subdomains showing the country name (newzealand.mysite.com) are more cost-effective and easier to obtain than official country-code TLDs (ccTLDs) with extensions (mysite.nz).

Are Subdomains Good for Search Engine Optimisation (SEO)?

So, what’s the deal with subdomains and SEO? The good news is that Google is cool with subdomains—it knows that they’re part of a primary domain, and the bots still can find and index the pages. That means it will rank your pages in the same way as it does with your main website.

The advantage of using subdomains is that you can optimise them for specific keywords. This helps you to target a new audience without distracting from the main purpose of your business. And by creating content on a wider variety of topics, you’ll be able to boost your site’s authority.

Subdomains also enable you to declutter your main site and organise the content by relevance, making it easier for visitors to navigate and find what they’re looking for. This improves the user experience, giving you more brownie points with Google.

Just be careful that your subdomain doesn’t cannibalise keywords from your main site—you don’t want the two sections to compete against each other.

So How Do I Get a Subdomain? Creating and Adding a Subdomain to Your Site In 4 Easy Steps

It’s pretty easy to create a subdomain, either with your domain registrar or your hosting provider (you may be using the same company for both). You can do this at any time after registering your original domain. The process will vary depending on your provider, but here are the key steps:

Choose a name

Come up with a subdomain name that describes the new section of your site, such as “blog”, “store”, “answers”, or “events”. It’s best to keep this to one word, which prevents your URL from becoming unwieldy. Remember that subdomains are limited to 63 characters, while the total domain name can have up to 253 characters.

Add the subdomain details

Next, log into your account with your hosting provider or registrar. The majority of providers use cPanel, a web hosting control panel software that lets owners manage their domain names.

There may be a dedicated menu for “Subdomains” or “Add Subdomains”, or a “Manage Domains” section. Select the relevant primary domain name from your list, and you should see an option to “Create Subdomain” or something similar.

Enter your chosen subdomain name, its parent domain or hostname, and any other information required. 

Add a DNS record

The next step is to create a new DNS (domain name system) record. Your provider may take care of this for you, but if not, look for an option like “Manage DNS,” “Edit DNS,” or “Advanced DNS.” Then navigate to “Add DNS” or “Add New Record”.

Enter the subdomain name, and specify where you want it to point to—either the IP address of the destination hostname or another domain name.

Submit the request

Once you’ve filled in all the relevant information, click “Submit” or “Create”. Now you’ll need to wait for the subdomain to be implemented. It may take as little as 30 minutes or as long as 48 hours for the DNS changes to spread across the Internet. 

Creating a Subdomain Has Never Been Easier With OnlyDomains’ Comprehensive, Reliable Software 

Subdomains are a handy way to organise your website and make it easier for visitors and search engines to navigate through your content. You can use them to diversify your offering, target a new audience, localise your content, or test a new feature or campaign,

OnlyDomains gives you unlimited subdomains with all its web hosting plans, and the user-friendly interface makes it incredibly simple to add them whenever you want to. (There’s great support available if you need it.)

You can also buy single or multiple domains from a list of 900+ global and local options or sign up for the website builder or business email package. So whatever you need to do with your website, get in touch to find out how OnlyDomains can help.

FAQs About What Is a Subdomain

Subdomains vs. subdirectories: I’m confused

In a similar way to a subdomain, a subdirectory is also a subset of the primary domain and a way of organising web content. The difference is that subdomains are treated separately from the main site, while subdirectories (sometimes called subfolders) stay within the main interface and have the same design.

There’s also a difference in their URL positions. As we know, subdomains come before the SLD. Subdirectories come after the TLD extension, separated by a forward slash. If you create a subdomain for your online store, the URL might be shop.mybusiness.com. But if you use a subdirectory, the URL would be mybusiness.com/shop

You can also add subfolders to the subdirectory for different categories, such as mybusiness.com/shop/mugs and mybusiness.com/shop/mugs/personalized. Another option is to add subdirectories to your subdomain, such as shop.mysite.com/mugs 

Should you use a subdomain or subdirectory?

It depends. If you have content that’s relevant to your main business purpose, it’s best to use subdirectories. For example, if you sell office stationery via officestuff.com, it makes sense to place notebooks in a subdirectory (officestuff.com/notebooks) as it fits with the main site. There’s no need to create a whole subdomain just for notebooks.

But for content that’s different from your main website, subdomains work better. Let’s say you’re diversifying into office furniture. In this case, furniture.officestuff.com is more obvious and specific than officestuff.com/furniture. It’s also sensible to use subdomains for content needing dedicated technical infrastructure.

Subdomains vs. subdirectories for SEO: which is better?

Both methods have certain benefits for SEO. Because subdomains act as separate entities, they give you more opportunities to optimise different types of content for specific keywords and audiences. They also enable simple navigation for users, which boosts your page rankings.

However, each time you create a subdomain, you’re starting from scratch with SEO. Google does realise that subdomains are part of the primary domain, but it treats them as separate websites. Even if your original site is high-ranking, the good reputation doesn’t rub off on subdomains.

Subdirectories do benefit from the main domain’s status. Because they’re part of your existing infrastructure, any authority earned by other website pages reflects on the subdirectories. This means you can rise up the rankings faster than you would with a subdomain. 

Are subdomains free?

This depends on your provider. Subdomains are usually included in the cost of your domain name registration or web hosting plan, often with the option to create unlimited subdomains. However, some providers charge an extra fee for subdomains.  

What is the most common subdomain?

It’s www, which was originally a requirement for all URLs but is now optional. Other popular subdomains include blog, shop, support, and mail.

What are good subdomain names?

A good subdomain name is one that instantly tells users what this section of the site is offering. For example, if it’s an online store, the most suitable subdomain would be “shop”. It should also be a short word that’s easy to type and remember—avoid using hyphens and special characters.