A domain name is, unquestionably, one of the most crucial elements of any website on the internet, and sub-domain is a small part of it.

Your domain is so much more than just a URL. It’s a virtual storefront for online shoppers to find your store and discover your brand and products. Moreover, a subdomain can be an effective tool to help you organize your website more efficiently, and when used correctly, will not negatively impact your website’s SEO

However, subdomains may be best used when you want the content to be private and not for your public sites. Whereas, A domain is used as a user-friendly address to access a specific virtual destination or website. Domains are also used for credibility and SEO.

What is a domain?

A domain name is a string of text that maps to a numeric IP address, used to access a website from client software. In plain English, a domain name is the text that a user types into a browser window to reach a particular website. For instance, the domain name for Google is ‘google.com’.

The actual address of a website is a complex numerical IP address (e.g., but thanks to DNS, users are able to enter human-friendly domain names and be routed to the websites they are looking for. This process is known as a DNS lookup.

Domains were created as a human-friendly way to access the Internet Protocol (IP), which represents a website’s online locator. An IP address is a string of numbers assigned to every computer, consisting of four decimal numbers ranging from 0 to 255 separated by periods. While these seemingly random series of numbers are great for computers, it’s much easier for humans to use words they can remember. And similar to saving a number on your phone, domain names allow us to save as google.com

All domain name registrations are overseen by the Internet Corporation for Assigned Names and Numbers (ICANN), which allocates and assigns IP addresses, runs accreditation systems for domain registrars and keeps a centralized database of all domain names and their IPs. As we’ll see in more detail later in this guide, the ICANN also has the authority to approve new domain extensions (also known as TLDs), manage them and shut them down if they don’t follow the determined rules.

It’s important to keep in mind that, while domain names are commonly referred to as URL (Universal Resource Locator) or web address, they’re actually just a part of it (albeit a crucial one). The basic form of a domain name consists of two elements: name and extension. In our case, “wix” is the name and “.com” is the extension. However, if you take a look at your browser’s address bar you’ll notice there are a lot more parts to it, all of which come together to make up this page’s web address. Take a look at the image below to see the function of each part of the URL.

How do domain names work?

Domain names are unique digital addresses that are easy for people to remember and use. When you enter a URL, your device sends a request to the global Domain Name System (DNS) network of web hosts. The DNS network then finds the unique IP address associated with the typed-in domain name and sends the device to that virtual destination, or website.

The domain name is unique to each website, and no two websites or businesses share the same domain name. For example, http://website.com and http://website.org are two separate entities. That’s because they end in different top-level domains (TLDs). The parts of the URL break down like this:

  • http://—protocol (not technically a part of the domain)
  • website.com or website.org—root domain
  • website—domain name
  • .com or .org—top-level domain

Personal care brand by Humankind’s root domain is byhumankind.com. So in this example, “byhumankind” is the domain name and “.com” is the TLD.

When you want to build an ecommerce website with your own domain (we recommend this!), you’ll need to do so through a domain registrar. Registrars serve as domain hosts or domain providers for your website. They do all the work in the back end to make your URL accessible to any internet user in the world who visits it. Your domain registrar will assign your domain its unique IP address.

Who manages domain names?

Domain names are all managed by domain registries, which delegate the reservation of domain names to registrars. Anyone who wants to create a website can register a domain name with a registrar, and there are currently over 300 million registered domain names.

What’s the difference between a domain name and a URL?

A uniform resource locator (URL), sometimes called a web address, contains the domain name of a site as well as other information, including the transfer protocol and the path. For example, in the URL ‘https://cloudflare.com/learning/’, ‘cloudflare.com’ is the domain name, while ‘https’ is the protocol and ‘/learning/’ is the path to a specific page on the website.

What are the parts of a domain name?

Domain names are typically broken up into two or three parts, each separated by a dot. When read right-to-left, the identifiers in domain names go from most general to most specific. The section to the right of the last dot in a domain name is the top-level domain (TLD). These include the ‘generic’ TLDs such as ‘.com’, ‘.net’, and ‘.org’, as well as country-specific TLDs like ‘.uk’ and ‘.jp’.

To the left of the TLD is the second-level domain (2LD) and if there is anything to the left of the 2LD, it is called the third-level domain (3LD). Let’s look at a couple of examples: 

For Google’s US domain name, ‘google.com’:

  • ’.com’ is the TLD (most general)
  • ’google’ is the 2LD (most specific)

But for Google UK’s domain name, ‘google.co.uk’:

  • ’.com’ is the TLD (most general)
  • ’.co’* is the 2LD
  • ’google’ is the 3LD (most specific)

*In this case, the 2LD indicates the type of organization that registered the domain (.co in the UK is for sites registered by companies).

How to keep a domain name secure?

Once a domain name has been registered with a registrar, that registrar is in charge of notifying the registrant when their domain is about to expire and giving them the chance to renew, ensuring they don’t lose their domain name. In some cases, registrars will prey on their users’ expired domain names by buying those domains the second they expire and then selling them back to the original registrant at an exorbitant price. It’s important to choose an honest and trustworthy registrar to avoid these kinds of predatory practices.

How to choose a domain name?

Naming your online store is an important and fun but daunting task. When you start an ecommerce business, it’s important to choose a domain name that represents your brand and is easy to remember but still unique so people don’t mix it up with other domain names. On top of that, you need to find a domain name that’s available and within your budget. When choosing your domain name, aim for the following:

  • Availability. Do a domain name search to see if your idea is available. If someone is actively using your domain name idea, you’ll likely need to find some new ones. If it’s unavailable and also not in use, you may be able to find out who owns the domain and negotiate a price.
  • Within budget. Available or not, domain names aren’t free. Common words and phrases—like headphones.com—are likely to be more expensive than less common words.
  • Easy to remember. Your domain name is what people enter into their browser to find your website. It’s important to make sure it’s easy not only to remember but also to spell—especially if yourbrand.com isn’t available.
  • On brand. Your domain name is a representation of your brand, especially if you’re selling online-only. Get your brand name somewhere in your domain name if possible.

What is a sub-domain?

A subdomain is an additional part to your main domain name. Subdomains are created to organize and navigate to different sections of your website. You can create multiple subdomains or child domains on your main domain.

For example: store.yourwebsite.com

In this example, ‘store’ is the subdomain, ‘yourwebsite’ is the primary domain and ‘.com’ is the top level domain (TLD). You can use any text as your subdomain, but you want to make sure it’s easy to type and remember.

While subdomains are technically part of the main domain, they exist almost independently. 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.

What is a subdomain used for?

Subdomains have many uses, including:

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, 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.

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. 

3. Optimize for mobile

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 $340 billion in sales last year in the US alone, and mobile shoppers spend an average $134 each purchase—a figure that’s trending upward. So there’s plenty of reason to consider the mobile shopper.

But mobile users have higher cart abandonment rates than people on other devices, clocking in at just over 85%. 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. Launch ecommerce

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 do shop.yourwebsite.com. Other common words include store or buy.

5. Contact

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.

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.

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.

Subdomains vs. subdirectories

Subdirectories are another similar form of subfolders that can be used as extensions of your main root domain. While a subdomain typically comes before the main domain in your URL, a subdirectory would come after. Using our earlier example, isellrefrigerators.com, if you were to add the store as a subdirectory instead of a subdomain, it would appear as isellrefrigerators.com/store.

There is much debate over whether subdomains or subdirectories are better when it comes to organizing your website and your many subfolders, especially in regards to search engine optimization. Let’s quickly look at some of the pros and cons of each.

Wrap up

The difference between a domain and a subdomain is that a subdomain acts as an extension of the domain. The domain represents a larger network of subdomains and webpages, while subdomains are a smaller subset of webpages that live at the same root domain.