What Is a Subdomain? A Complete Guide

Ever visit a website and notice a small extension at the front of the URL? You may have typed it in manually or been automatically redirected. These extensions are subdomains, and subdomains have several applications in your ecommerce business strategy. ​​

What is a subdomain?

A subdomain is an optional part of an internet domain name that appears before the root domain and top-level domain (TLD). A common subdomain is “www” and often simply a specific directory on the server. Subdomains are commonly used to separate distinct functions of a website, such as a blog, shop, or member’s only area.

A subdomain is an extension of the primary domain, dedicated to a specific function or purpose. While most domain names are written as www.domain.com—for example, www.wikipedia.com—subdomains have a prefix that sends the user to a different destination. The subdomain might look something like shop.website.com or country.website.com.

While subdomains are technically part of the main domain or TLD, they exist almost independently. Think of them as an extension of your main website. You can change the look and feel for your subdomain page to distinguish it from your main domain, or you can keep the look and feel the same to maintain a consistent brand experience. Subdomains can be incredibly effective for ensuring your quality content is seen by the right users, which ultimately can help with search engine optimization.

Is a subdomain a separate website?

A subdomain is not a separate website, but it’s somewhat treated as such by Google. Subdomains should not be confused with top-level domains or a second-level domain.

Subdomain vs. domain: What’s the difference?

Subdomains are a smaller subset of web pages that live at the same root domain. The domain is the larger network of all subdomains and web pages.

A subdomain, in effect, acts as an extension of a domain.

What is a subdomain used for? 8 popular use cases

Subdomains have many uses, including:

1. Selling internationally
2. Site testing
3. Optimizing for mobile
4. Launching an ecommerce site
5. Contact page
6. Client portal
7. Blog
8. Targeted selling

1. Selling internationally

Subdomains can help you stay organized and create location-specific experiences when you sell internationally. Your subdomain extension may be the abbreviation for the region, country, or continent. For example, you might use uk.website.com for shoppers in the UK and ca.website.com for Canadian-based customers. When you use a subdomain for each location, you appear more relevant and legitimate, giving shoppers more reason to trust your brand. You can use multiple subdomains if you sell in several countries.

You might also use the subdomain to accommodate different languages. The Spanish version of your website could be es.website.com, and French could be denoted as fr.website.com. This could be a more approachable way to manage your subdomains or subdirectories, since multiple countries/regions speak Spanish and multiple countries/regions speak French.

It all depends on the context of the website and what the experience is going to be like for the user. If you have country-specific pricing or shipping rules, for instance, you’ll want to use a subdomain for each country. But if it’s simply a matter of translating your website and making other content adjustments, you might look to use language-specific subdomains.

 BioLite sells stoves, portable power stations, and other outdoor gear to customers all over the globe. The website gives users the option to self-select their location, choosing from the UK, the US, Canada, Europe, and other locations. Each has its own dedicated subdomain indicating which region the site is for. UK customers are taken to uk.bioliteenergy.com, while US shoppers head to bioliteenergy.com. Canada and Europe are ca.bioliteenergy.com and eu.bioliteenergy.com, respectively, while all other regions go to row.bioliteenergy.com.

2. Site testing

Many ecommerce businesses use subdomains to create testing sites. These subdomains allow you to test your website or individual pages before you push them live. This is important because it lets you find and address any issues or bugs before the public has access—you can launch most new campaigns with confidence.

It might also be the case that you’re still building your site or aren’t yet ready to fully invest in it. Free Shopify users, for example, get a URL with myshopify.com at the end as the domain name—so the merchant’s store name actually acts as the subdomain. When ready, you can upgrade to a paid plan and own the domain name—and perhaps create your own subdomains down the line as well.

3. Optimizing for mobile

Subdomains can also be useful for improving the mobile version of your website.

If you shop online using your smartphone, you may have noticed a letter m at the beginning of some site URLs. This is because those sites use a dedicated mobile subdomain for users on phones, tablets, and other small devices.

It’s important to create tailored mobile ecommerce experiences that differ from those your customers have on a desktop browser. Mobile responsiveness is the bare minimum—especially considering the opportunity online brands have when it comes to engaging mobile shoppers. Mobile commerce hit nearly $360 billion in sales in 2021 in the US alone, and mobile shoppers spend an average of around $112 each purchase—a figure that’s trending upward. So there’s plenty of reason to consider the mobile shopper.

Creating a dedicated mobile website using a subdomain, such as the letter m, is one way to tailor your mobile experience without impacting the desktop experience.

4. Launching an ecommerce site

Not every ecommerce site started as an ecommerce site. Some websites start for other reasons. Your website may have originated as a blog, for example, and after building a solid audience you may have decided to monetize your blog through ecommerce. Or you could have launched an affiliate site that you later want to add an ecommerce arm to.

Some websites migrate to another software that’s built specifically as an ecommerce platform. But others don’t bother with migration and instead create a dedicated subdomain for ecommerce specifically. Many websites use “shop” as their subdomain—so you could have shop.yourwebsite.com. Other common words include “store” or “buy.”

Lady Gaga uses this approach to differentiate her regular website from her ecommerce site. When you visit ladygaga.com, you see lots of different content—not necessarily products for sale. That’s because someone visiting a celebrity’s website may not initially think of buying something.

But people who click Shop, or shop.ladygaga.com likely are interested in buying something and expect to see lots of items for sale. Lady Gaga keeps her ecommerce entity separate from her main branded site, making sure to provide something for everyone.

5. Contact page

Your Contact Us or tech support pages may also warrant a new subdomain, especially if your tech stack demands it. Endy mattresses uses a subdomain for its Contact page, answers.endy.com. You could also use words like “support,” “help,” or “contact.”

6. Client portal

Similarly, you might have a client portal your customers can sign in to. Client portals are nice for shoppers because they can sign in to check on order status, previous orders, current promotions, loyalty program status, and more. And it’s nice for brands because customers are empowered to check on their order themselves, instead of taking time from your support staff every time they want an order update.

Seea doesn’t use a subdomain for its client portal, but the sustainable swimwear brand has a separate subdomain dedicated to returns and exchanges. Users visit returns.theseea.com to initiate a return or exchange. You’ll notice this subdomain has significantly limited functionality when compared to the main site, because it’s meant for one specific purpose.

7. Blog

Some websites use a subdomain to separate their blog from the rest of the website experience. In many blog examples, the subdomain has distinct functionality that varies from the rest of the site. If you want to start a blog for your website, you may consider hosting it on a subdomain of your main site.

The Who Gives A Crap blog lives at blog.whogivesacrap.org, while the main domain is simply whogivesacrap.org.

8. Targeted selling

You can use subdomains to appeal to different audiences or business goals. You could create subdomains for specific customer segments or create a subdomain to rank for specific keywords.

GRAV has a subdomain for selling wholesale that lives separately from its consumer-facing site. While its regular domain name is grav.com, wholesale buyers will go to wholesale.grav.com.

3 subdomain examples

Now that you understand some common use cases for subdomains, let’s look at some examples in the wild:

1. Amazon 

While the majority of Amazon users simply head to www.amazon.com when looking to shop online, Amazon is known for its extensive subdomains.

For example, the subdomain aws.amazon.com directs visitors to a page dedicated specifically to all things AWS. Head to music.amazon.com and you’ll find a page covering Amazon’s music streaming service. Amazon uses subdomains to help ensure it can share targeted content and solutions based on its diverse user base.

2. Shoe Zero affiliate program

Shoe Zero, a Shopify merchant that allows customers to customize the design of their own shoe, uses the main domain shoezero.com for its website. It also has an affiliate program. Members of the program can log in and manage their account at Shoe Zero’s chosen subdomain of af.shoezone.com.

The subdomain is designed to keep its affiliate program and member details separate from its customer data.

3. Shopify help center

At Shopify, the subdomain help.shopify.com is a dedicated landing page for users needing assistance with the suite of Shopify products. While the community can access the help center through Shopify.com, help.shopify.com helps keep everything streamlined for those needing assistance.

Although not every brand will ultimately need a subdomain, they can be great to use when looking to publish tailored content.

How to create a subdomain

While the steps to create a subdomain will vary slightly depending on who you use for web hosting, creating a subdomain usually involves making some slight changes within the settings of your domain registrar and hosting provider. During the process, you may come across terms such as a record and cpanel.

If you’re using WordPress, here’s an excellent resource for adding a subdomain. If you’re using Shopify, everything you need to know on how to set up subdomains is in this step-by-step tutorial.

Steps

1. From your Shopify admin, go to Settings > Domains.
2. Click Manage for the domain you want to configure.
3. In the Subdomains section, click Add subdomain.
4. Enter the prefix you want to add: For international subdomains, enter the two-letter country code for your target market. For example, “eu” for Europe, or “ca” for Canada. For all other subdomains, enter the text that you want to add as a prefix. For example, “blog” or “shop.”
5. Click Add subdomain.

Launch your domain (and subdomains) with Shopify

Managing a domain is complicated enough without throwing subdomains into the mix. That’s why you need a tech stack that simplifies everything in the back end for you.

When you register your domain and subdomains with Shopify, it immediately connects to your online store—no third-party apps or complex setup processes necessary.