What is localhost?

We use languages to communicate with each other. However, some vocabularies are too specific for some situations or subjects, like computer terminology. If you want to learn about networking, it’s important to understand the language that you’ll run into. No better place to start, than learning what is localhost.

So what does localhost mean?

In computer networking localhost refers to a computer running a program. The computer works as a virtual server. In this sense, the computer is not a physical object but a system that runs inside. If that is difficult to understand, consider localhost as a way to ‘call’ your computer in the context of networking. address

Localhost is not only a term but can also be a domain name, like or It’s an address. If typing in a browser directs you to Google’s main page, where will localhost take you? It will take you to your computer. This situation is also known as a loopback address.

Like any other domain name, localhost also has an IP (Internet Protocol) address. The address ranges from to, but it’s normally Trying to open in an IPv4 connection will trigger a loopback. You can also start a loopback in an IPv6 connection by entering :1.

Fun fact: the first section of the address – 127 – is reserved only for loopbacks. For that reason, Transmission Control Protocol and Internet Protocol (TCP/IP) immediately recognizes that you want to contact your computer after entering any address that starts with these numbers. That is why no websites can’t have an IP address that begins with 127. If initiated, this action will create a loopback device; which is a virtual interface inside your computer’s operating system.

What is the purpose of localhost?

So what can you do with localhost? Despite its simple meaning, localhost is useful if you are a computer technician. Generally, there are three advantages that loopback offers:

  • Speed Test
    As a network administrator, you will want to make sure that all equipment and the TCP/IP are in top condition. You can do a connection test by sending a ping request to the localhost. If you are using Windows, for example, you can open the command prompt and enter “ping localhost” or “ping”. The test will show how well everything performs, and you can immediately fix any problems that occur.
  • Program or Web Application Test
    Contacting localhost also serves a purpose for developers; especially if they are creating web apps or programs that require an internet connection. If you still remember, your operating system becomes a simulated server once a loopback is triggered. Thus, you can load the necessary files of a program into the server and check its functionality.
  • Site Blocking
    There is another interesting trick that you can do by using loopback – blocking websites that you do not wish to access. Loopback is useful for preventing your browser from entering harmful sites, like ones containing viruses. Before learning how this works, however, you need to know what “hosts file” is and its role in this context. As you already know, all websites have an IP address. You can enter a website because the DNS or Domain Name System searches for the appropriate IP address under which the website is registered. Your computer helps improve this process by storing a hosts file for every site you have visited. This file contains the IP address and the domain name of a website. You can change the IP address into and voila, the site which hosts file you modified redirects you to localhost instead. An example could be a company’s computer admin blocking access to a website.

Just before going online make sure that you’re with the best hosting provider. Here, at Hostinger, we’re offering best-in-class web hosting services. Also, 30-day money-back guarantee is included.

Learn More


Now you understand that localhost is not merely a technical term for your computer. It is a domain name that enables you to do some testing and even close access to websites. If you aspire to be an IT technician, it is essential to know how to use a loopback according to your needs.

The Author


Aldwin N. / @aldwin

Aldwin is a digital content writer at Hostinger. Specializing in web hosting and WordPress for years, he is eager to help people uplevel their business on the internet. Apart from being a tech junkie, Aldwin likes fiction and photography.

Related tutorials

Leave a reply




This site uses Akismet to reduce spam. Learn how your comment data is processed.

Become a part of Hostinger now!

More in Glossary
What is WordPress Database: All You Need to Know