How to get domain name from URL in JavaScript

What is an URL?

A URL is another name for a web address. For instance, a word-based URL is Javatpoint.com. A URL can also be created using an IP address (ex. 192.168.2.24). Most consumers provide the name's address when conducting an online search because names are easier to remember than numbers.

Web browsers use URLs to ask web servers for particular pages. Below is a list of a URL's syntax and format.

Syntax

Parameters

Scheme-

The type of Internet service is specified (http or https is being used in general).

Prefix-

It establishes a domain prefix (www is the default for http).

Domain-

It discusses the domain name on the internet (ex. javatpoint.com).

Port -

It identifies the port on the host (80 is the default for http).

Path -

It creates a path on the server side.

Filename -

It identifies a resource's or document's name.

Getting the domain name from a URL in javascript can be a useful task for various reasons, such as extracting the domain name for web analytics or security purposes. In this answer, we'll explore different ways to extract the domain name from a URL in javascript, along with their pros and cons.

1. Using the window.location object

The most straightforward way to get the domain name from a URL in javascript is to use the window.location object, which provides information about the current URL. The window.location.host property gives us the domain name, including the port number if it's present. Here's an example:

This approach has the advantage of being simple and reliable. However, it only works for the current URL, so if you need to extract the domain name from a different URL, you'll need to use a different method.

2. Using the URL constructor

Another way to extract the domain name from a URL in javascript is to use the URL constructor. It is a built-in javascript object that can parse a URL string and provide access to its various components. Here's an example:

The URL constructor has the advantage of being able to extract the domain name from any valid URL, not just the current one. However, it's only available in modern browsers, so you'll need to check if it's supported before using it.

3. Using regular expressions

A more advanced approach to extract the domain name from a URL in javascript is to use regular expressions. Regular expressions are a powerful tool for pattern matching, and we can use them to extract the domain name from a URL. Here's an example:

This regular expression pattern matches the domain name in a URL, ignoring the protocol (http or https), username and password, and path. It works by looking for the first occurrence of a sequence of characters that doesn't include a colon, a slash, or a newline, preceded by an optional protocol, username and password, and optional "www." prefix. The match method returns an array containing the entire match and any captured groups, so we need to extract the second item (at index 1) to get the domain name.

This approach has the advantage of being flexible and adaptable to different URL formats, but it's also more complex and prone to errors if the regular expression pattern is not precise enough.

4. Using the DOM

Finally, we can also extract the domain name from a URL in javascript by using the DOM. We can create a hidden anchor element, set its href attribute to the URL we want to extract the domain name from, and then read the hostname property. Here's an example:

This approach has the advantage of being easy to understand and implement, but it also creates a DOM element, which may have some performance implications if you need to do this repeatedly.

Conclusion

There are different ways to extract the domain name from a URL in javascript, and the best approach depends on your requirements and constraints. If you only need to extract the domain name from the current URL, using the window.location object is the simplest and most reliable method.