When to Use It, Pros and Cons, and More

Find the domain name and extension TLD it is essential when create a website. In any case, this process can seem daunting, since there are more than 1.5 thousand options of top-level domains (TLDs) available to choose from, such as .with and .io.

.io is a country code top-level domain (ccTLD) referring to the Chagos Archipelago, which is part of the British Indian Ocean Territory (BIOT). However, it has become a generic domain and is very popular in the technology world, as IO or I/O means input/output in computer science.

Each TLD serves a specific purpose. For example, .com domains are suitable for commercial websites as well as the domain registration .com.br is for sites that want to stand out in Brazil. Meanwhile, domain names .io are more popular among technology corporations.

This article will specifically discuss the .io domain extension, from its definition to a brief history of its functions. We’ll also list the pros and cons of owning a .io domain name to help you decide if this is the best option to use for your website.

The Internet Assigned Numbers Authority (IANA), the organization responsible for administering the Domain Name System (dns), designated the administration of the TLD .io for the Internet Computer Bureau (ICB) company. Later, Levis Strauss registered the domain name levi.io for a purpose other than geographic identity.

Now the TLD .io is operated by affiliatesa US private registrar that also manages the domains .mobi and .info.

When Should You Use the .io Domain Extension?

Compared to other popular top-level domains, the TLD .io is used by few websites, but this domain extension is becoming more and more common among technology and high-traffic websites.

Below are just a few examples of popular .io sites:

  • opensea.io – the largest virtual marketplace for NFTs.
  • etherscan.io – website used to search Ethereum blockchain transactions.
  • greenhouse.io – Applicant monitoring system and recruitment software.

despite the .io being popular in the technology industry, this extension is available for any type of business. Generally, visitors see this TLD more as a generic domain than a country-specific one (common examples of these cases are .com.br and .co.uk).

Consequently, Google treats the domain extension .io as one of your Generic Country Code TLDs. that is, ccTLDs that are known to be used generically, not country-specific.

Note that the TLD .io is different from .lywhich is still administered as a country code top-level domain for Libya — although many businesses outside the country also use this extension, such as the popular ones bit.ly and Wow.ly.

Therefore, using the domain extension .io is one of many tricks for global companies to come up with a memorable brand name. These companies do not need to be located in the Chagos Archipelago to register domains .ionor do they need to worry about search rankings, as they are not country-specific.

For example, Marco Rubio successfully used the rub.io domain for his US presidential campaign. Another example is the Bricklinka platform for buying and selling LEGO bricks, which uses the domain stud.io to redirect visitors to your studio software (studio).

Screenshot of the Studio section of the Bricklink website

Other examples of using the .io TLD for different purposes are those related to Italian and Esperanto speakers. They use the .io to create geographically relevant and user-friendly domains for top keywords. “Io” in Italian means “I”, and so it acts as a suffix at the end of official names of lands and countries.

To illustrate, the domain Esperant.io redirect visitors to the website Free Folioa newsletter written in Esperanto.

Libera Folio website home screen

What Does .io Mean for Startups?

SaaS and tech startups use domain names .io because of the TLD’s reference to input/output terminologies, providing a single word that is relevant and recognizable to the public and startup industry communities. In addition, extensions .with may not be available for your second-level domains, making .io a perfect alternative.

What Does .io Mean for Tech Companies?

Similar to startups, other companies in the technology industry use the TLD .io to refer to the terms input/output. These brands include open source organizations and corporations in the financial services industry, such as cryptocurrency companies.

Many video game projects also use the extension .io in their domains, as the term “io” in the gaming scene refers to browser-based games with multiplayer components and minimalist graphics.

Browser game screenshot with URL highlighting

Pros and Cons of .io Domain Extension

Now that you know the basic concept and know what .iolet’s look at the advantages and disadvantages of using this TLD in your online address.

Pros of a .io Domain

Here are some great reasons why many people use domain extensions .io:

  • Relationship with the tech world – the extension .io is recognizable in the technology environment and in startup communities. This makes the domain name efficient for external communications, helping it to be quickly and easily recognized by many people in the industry.
  • Greater availability – compared to other domain extensions such as .com and .netaddresses ending in .io represent only 0.6% of all existing domains on the internet. As such, the domain name you want to buy for your brand is more likely to be available with that TLD rather than the more popular ones.
  • Great recognition by search engines – Google does not list the domain extension .io with the British Indian Ocean Territory. This means that the search engine does not target or target that specific geographic region when it displays sites .io in your search results.
  • Possibility to be creative with the name – use the extension .io to shorten your URL and create more attractive and memorable domains.

Cons of a .io Domain

As long as the TLD .io offer many advantages, this domain extension also has some disadvantages, including:

  • highest price – you costs of registration and renewal of a domain name depend on its length, availability and popularity. The TLD .io is more expensive than .online domains, .techor .with. One of the reasons that explains this is that the .io domain extension has become a current trend, being in high demand in the technology industry by startups.
Screenshot of a .io domain search in Hostinger's domain checker, with alternative indications
  • Less reliable and less memorable – compared to other options such as .with and .orga domain extension .io it has lower reliability and is less memorable. Your confidence score is only 3.0 and it has a memorization rate of approx. 28%. This can be explained by many reasons, including the fact that the TLD .io is relatively new, so it doesn’t yet have the same credibility and reputation as traditional extensions like domains .with.
  • political controversies – There are some geopolitical problems between the Chagos Archipelago, the United Kingdom, Mauritius, and the United States of America. The dispute for the current BIOT territory can trigger the deactivation of the country and domains IO ISO-3166 code .io — something similar to what happens to some businesses in the UK, which are no longer able to renew or register .eu domain names since the country’s exit from the European Union with Brexit.


If you opt for the .io domain extension, remember to buy your domain with a reputable and reputable registrar like Hostinger — after all, don’t forget that there are controversies with that TLD. All of our domain names have privacy protection and 24/7 support from our experts. Alternatively, go to hosting sites of your trust and acquire services that guarantee the complete functionality of your website.


the domain .io It used to be just a country code TLD, specifically for Indian Ocean location sites. However, once it’s sold, it’s no longer country-specific, and Google considers it a generic top-level domain — one that serves multiple purposes and reaches a wider audience.

Many people consider the .io as the right domain extension for your technology and finance companies, alluding to computational input/output processes. At the same time, other businesses acquire this different TLD to make their domain names more creative and relevant.

Despite being more expensive, less reliable and involved in complex geopolitical issues, domains .io have more availability than traditional TLDs and offer the possibility of a shorter name for websites. This option also helps people to associate sites .io to technology companies and startups, even before viewing their content.

We hope that this article will help you decide if it is suitable to use the domain extension .io on your website. Remember to register your desired domain while it is still available and through a reputable registrar or hosting provider.


Bruna graduated in international relations from UFSC and is currently doing a master’s degree in sociology from UFRJ. Determined to make technology knowledge accessible to everyone, she works as a freelance translator and writer at Hostinger. She has experience with translation, localization, copywriting, project management, customer service and academic writing. In her free time, she likes to watch series, cook and play logic games.

Leave a Comment

Your email address will not be published. Required fields are marked *