What Does .io Mean & Why Tech Companies Use It

What Does .io Mean: Understanding the Tech-Savvy Domain Extension

Article's banner

“.io” is a generic top level domain that stands for “Input/Output”. The “.io” domain extension is used to denote web addresses or online services that receive user input, process it, and then provide output back to the user.

For example, an online store would take input from customers (e.g., what items they want to purchase) and provide them with output (e.g., a receipt for their purchases).

The .io domain extension is becoming increasingly popular among web developers and startups, but still, the average tech user doesn’t know the answer to “What does .io mean?”.

In this article, we will explain more about what .io means and why it has become so popular, and how it relates to your website.


Choosing the right Domain Hosting provider is crucial for ensuring your website is reliable and fast. For a detailed guide, check out our list of the best Domain Hosting providers.

Best Domain Hosting Choices

ProviderUser RatingBest ForExpert & User Reviews 
 5.0VersatilityHostArmada ReviewVisit HostArmada
 4.9CustomizationUltahost ReviewVisit Ultahost
4.6SpeedHostinger ReviewVisit Hostinger
  • “‘.io’ stands for ‘Input/Output’”
  • Startups and tech companies are most likely to use .io
  • Many famous companies use .io because it’s a memorable domain and implies modernity
  • .io domains can be expensive, but there are many cheap options and loopholes
  • Registering a .io domain is easy, but choosing to do so is up to you

What Does .io Mean in an URL?

IO (Input/Output) is a term used in computer science to describe the process of taking data from a user (the input) and then providing the user with some kind of information or result (the output).

For example, when you type something into Google, it takes your input and provides you with search results as its output.

The .io domain extension has become popular among tech and SAAS startups because it suggests that they offer an online service that works by taking input from users and providing them with some kind of output. It also implies that their service is cutting-edge and modern, which is appealing to many tech-savvy customers.

What Country Uses a .io Domain?

Officially, the .io domain name is assigned to the British Indian Ocean Territory. This is an overseas territory of the United Kingdom located in the Indian Ocean between Africa and Indonesia. It has been a member of the Commonwealth since 1983 and is home to more than 3,000 people.

Can .io Domains be Used Outside of British Indian Ocean Territory?

Yes, .io domain names are not country-specific and can be and are used outside of the British Indian Ocean Territory.

Despite its official status as part of the UK, many tech companies have chosen to register websites using .io domain extension although they are not geographically relevant.

This is because it implies that they offer some kind of online service or product. Its association with cutting-edge technology also makes it appealing for tech startups looking to make a memorable impression on their customers.

What Is the .io Domain Used For?

.io domains aren’t typically the first generic domain or generic top-level domain name that people turn to when they make their website. However, the websites that do use them tend to find great success. 

W3Techs reports that although far fewer sites use .io, the generic top-level domain name is used by higher-traffic sites than .net, .com, .org, and other generic top-level domains. (as of September 2023).

.io is the perfect domain for:

  • Open Source Projects - Projects that are available for anyone to use or modify
  • Browser Games - Games that can be played directly in a web browser
  • Personal Blogs or Portfolios - Pages created by individuals to share their work or ideas
  • Online Stores and E-Commerce Sites - Websites that allow users to purchase products online
  • Startups and Tech Companies - Companies that are just starting and trying to make their mark in the computer science and tech world

Who Uses .io Domain Names?

The .io domain extension is mostly used by startups and tech companies that want to give their website a modern, cutting-edge feel.

Many of these companies are focused on developing online services that take input from users and then provide them with output such as search results, products, or information.

The .io domain’s appeal also extends to its brevity and memorability, making it ideal for creating sleek, catchy, and easy-to-recall web addresses. This characteristic aligns perfectly with the agile and dynamic nature of startups and tech ventures, helping them establish strong online identities.

In essence, the .io domain has become a symbol of innovation, technological prowess, and a commitment to delivering high-quality digital experiences.

As the digital landscape continues to evolve, we can expect to see more startups and tech companies embracing this extension to convey their dedication to pushing the boundaries of what’s possible in the online realm.

HostArmada: The Best Domain Hosting
HostArmada offers a wide range of Domain TLDs at affordable prices that come with DNS management and email forwarding. They offer a free domain forever as part of all their hosting plans. HostArmada is an excellent solution for anyone looking for a reliable domain registrar and the convenience of managing websites and domains from a single place.
Visit HostArmada

What Famous Brands Have .io Domains?

Many memorable brand names have chosen to use .io domains. Some examples of popular .io sites include:

  • Airbnb (https://airbnb.io/) – A website for finding and booking unique accommodations around the world
  • Agar.io (https://agar.io/#ffa) – An online game where players compete against each other to become the largest cell on the board
  • Sketch.io (https://sketch.io/sketchpad/) – An online tool for creating and sharing digital drawings
  • Notes.io (https://notes.io/) – A website for creating and sharing digital notes

These companies all use .io domains because they are associated with cutting-edge technology and modern services, which is something that many of these brands want to project to their existing brand customers and potential clients alike. They show that you can use .io domain extensions to create your own memorable brand names.

Why Is .io So Popular?

The .io domain name has become one of themost popular domain extensions among tech companies and startups because:

  • It implies that the service is modern and cutting-edge, which is appealing to many tech-savvy customers
  • io domain name is relatively inexpensive compared to other top-level domains like .com or .net. The cost can start from $47.99 for the 1st year. This makes it a great option for smaller businesses who may not have the budget to purchase more expensive domains.
  • The simplicity of the two-letter “.io” extension makes it easy to remember and type out
  • It’s a keyword-friendly domain name in most cases. This helps make the URLs of .io websites more memorable for customers, which can help increase traffic to the website.

What’s the Difference Between .ai and .io Domains?

The .ai domain extension stands for “Artificial Intelligence” and is used by companies that specialize in AI-related services. For example, a company offering facial recognition software may use the .ai domain to indicate that its service uses machine learning algorithms.

In contrast, the .io domain extension implies that a website or online service takes input from users and then provides them with some kind of output. This could be anything from displaying search results based on user queries to providing recommendations for products or services.

Should You Buy a .io Domain Extension?

The decision to purchase a .io domain name should be made based on your individual needs and goals regarding relevant domain utilization. Let’s go through some important information to give you a baseline for making your domain-ending choice.

Pros & Cons of .io Domains


  • Suggests that your online service is modern and up-to-date
  • Quickly conveys the idea of input/output to the user
  • Easy to remember and type in a website address bar
  • Short domain names are desirable for branding purposes


  • Not as widely recognized as .com domains, so users may not recognize it as quickly
  • May be more difficult to reach wide search engine recognition
  • May be more expensive than other lesser-known domain extensions

Are .io Domains Safe?

Yes, a .io domain name is generally safe. The io domain name and extension is managed by the British Indian Ocean Territory, which has a strong track record of security and of top-level domain reliability.

Furthermore, all .io domains must be registered through an accredited registrar that is vetted for safety and security.

Do .io Domains Rank in Google?

Yes, .io domain names are treated just like any other domain extension by Google and other search engines. They do not have any special ranking privileges and they generally have the same credibility as other domains.

Why Are .io Domains Expensive?

.io domain names can be expensive because they are in high demand and there is limited availability of them.

They are becoming increasingly popular among tech startups and companies, so the demand for them is increasing. Additionally, many people find .io domains to be catchy and memorable domains, which makes them even more desirable.

Finding Cheap .io Domains

If you’re looking for a cheap .io domain name, here are some domain hacks that can help:

  • Search online for coupon codes and discounts from domain registrars, like NameCheap
  • Check out marketplaces like Flippa where you can buy and sell domains
  • Look for resellers who specialize in selling .io domains at discounted prices, like Name.com
  • Consider registering multiple related or matching domains to lower the cost per domain. Hover is great for this

How & Where to Register a .io Domain

Registering a .io domain name is surprisingly straightforward. Here are the steps you need to take:

  1. Go to a domain registrar, such as IONOS or GoDaddy, and search for available .io domains
  2. Select the one you want to register and add it to your cart
  3. Enter your payment information and complete the purchase process
  4. Your new .io domain will be ready in just a few minutes
  5. Create your .io page with the best website builders

Final Word: Is .io Domain Right for You?

The .io domain extension implies that your company is modern and cutting-edge. This can be appealing to some customers. However, other domains such as .com or .net may command more respect. Ultimately, the decision of which domain extension is best for you is up to the needs of your business.

Ultahost Domain Hosting
UltaHost delivers customized hosting solutions for everyone, from beginners to industry giants, emphasizing superior VPS and managed hosting services for hassle-free website functionality. Ultahost offers a free domain, SSL, and many great features, but what really makes it stand out are its highly transparent pricing plans and all the included freebies.
Visit Ultahost

Next Steps: What Now?

Frequently Asked Questions

What does .io mean on a website?

“.io” stands for “Input/Output” and is used to denote a website or other online service that uses input from users, processes it in some way, and then provides output back to the user.

What does the IO stand for?

IO stands for Input/Output.

10 Best VPS Hosting on Reddit: Most Recommended Providers 2024

Reddit is a popular source for hosting recommendations, including VPS hosting. With multiple conversations on choosing a service and dozens o...
4 min read
Ela Gal-Kfir
Ela Gal-Kfir
Digital Marketing Specialist

HostAdvice Speaks to ScalaHosting: An Interview with Chris Rusev

HostAdvice had the opportunity to speak with Chris Rusev, the CEO and co-founder of , a web hosting company that offers shared, cloud VPS, and res...
8 min read
Eddie Segal
Eddie Segal
Digital Marketing Specialist

Email Deliverability: What Is It, Key Factors & Best Practices

What is Email Deliverability? Think of it like mailing a letter and making sure it lands right in the recipient's hands, not lost or thrown...
17 min read
Ela Gal-Kfir
Ela Gal-Kfir
Digital Marketing Specialist

Email Marketing vs. Social Media: Which is More Effective?

What is Email Marketing? Email marketing is a  that involves companies reaching out to potential and existing customers via email ...
10 min read
Ela Gal-Kfir
Ela Gal-Kfir
Digital Marketing Specialist
HostAdvice.com provides professional web hosting reviews fully independent of any other entity. Our reviews are unbiased, honest, and apply the same evaluation standards to all those reviewed. While monetary compensation is received from a few of the companies listed on this site, compensation of services and products have no influence on the direction or conclusions of our reviews. Nor does the compensation influence our rankings for certain host companies. This compensation covers account purchasing costs, testing costs and royalties paid to reviewers.
Click to go to the top of the page
Go To Top