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Home Guide How to enable JavaScript in your Browser: A Detailed Guide

How to enable JavaScript in your Browser: A Detailed Guide

By Mohit Joshi, Community Contributor -

JavaScript backs a good amount of credit behind most of the aesthetically appealing web pages you see on the internet. Every web developer is aware of JavaScript, and its crucial role in web page design. However, have you ever considered why JavaScript is important in the context of web browsers? It is essentially important for enhancing user experience, emphasizing the interactivity and dynamic behavior of web pages. 

In this article, let’s explore and leverage JavaScript’s complete potential to access top-notch features of web development. 

What is Browser JavaScript?

Browser JavaScript is nonetheless different from the ordinary JavaScript that we use in our regular development, except that while referring to Browser JavaScript, we are talking about implementing JavaScript programming language that runs within a web browser. The browser’s specific engine, known as the JavaScript engine is responsible for rendering the JavaScript code for executing specific instructions. 

Some of the popular web browsers and their JavaScriupt engines are as follows, V8 for Google Chrome, Chakra for Edge, Spider Monkey for Mozzila Firefox, and more. With the rising popularity of JavaScript, some JavaScript libraries and frameworks have also emerged to innovate modern web development by introducing advanced features. Some of these frameworks are, React, Angular, Vue, and more. 

How does it work?

The main role behind the successful operation of Browser JavaScript is of JavaScript engine. JavaScript engines conduct the following processes to execute JavaScript code in the browser to attain interactive and user-friendly web pages

jS source code

  • Parsing:  If any web page contains the JavaScript code, once it is loaded, the parser reads and converts the JavaScript code into a structure called Abstract Syntax Tree (AST), which is also referred to as the code’s syntax.
  • Compiling: Once the JavaScript code has been converted into an AST, it is then either compiled into bytecode or machine code, depending on the target platform. This is done because bytecode is faster to execute and machine code is the native language that the machine hardware understands.
  • Executing: After the JavaScript code is compiled it is all set to be executed in the browser.
  • Interacting with Browser: JavaScript performs several events in the browser, such as manipulating API, handling DOM, making HTTP requests, and more. All these interactions of JavaScript with the browser with the help of APIs and interfaces. 

What can in-browser JavaScript do and cannot do?

Browser JavaScript opens a wide world of accessing powerful functionalities of a web browser. However, with such powers, there come several limitations. Let’s delve into how browser JavaScript supports modern web development pillars. 

Benefits of in-browser JavaScript

  1. A lot of interactive components that you see on the web are created with the help of JavaScript, therefore, it plays a vital role in creating the interactive components for the web. 
  2. It can help in speeding up the communication between the client and the servers, with the help of advanced technologies like AJAX (Asynchronous JavaScript And XML), which helps in retrieving data without having to fully reload the webpage. 
  3. JavaScript also helps in handling user inputs such as clicks, hovers, form submissions, and more. 

Limitations of in-browser JavaScript

  1. In-browsers’ JavaScript is unable to access the hardware devices and has no control over them. 
  2. JavaScript is not capable enough to modify or change the browser’s settings, such as extensions, homepages, and more. 
  3. JavaScript is also unable to access the local file system, which also makes it less secure as it is unable to delete files on the local machine that are private to any user. 

What makes JavaScript unique?

JavaScript is one of the most popular programming languages across the world, but what is in JavaScript that makes it so unique and sets it apart from other programming languages? 

  1. In order to create interactive and dynamic online pages, JavaScript was created specifically for web browsers and may be used directly in web browsers. 
  2. Almost every web browser understands JavaScript, therefore, it makes JavaScript an ideal choice for web development. 
  3. JavaScript is a vast language that contains several tools, libraries, and frameworks and is evolving at a continuous speed for new features and improvements to enhance modern web development. 

Why should you enable Javascript in your Browser?

We have discussed so far the importance of in-browser JavaScript. Almost every web browser that is present in the world supports JavaScript, however, let’s now delve into why we should enable JavaScript in the browser. 

  1. The interactive and dynamic elements of many websites depend on JavaScript, therefore you won’t be able to use them if JavaScript isn’t enabled in your browser. This is helpful for real-time communication with online apps.
  2. JavaScript is widely used by developers to access modern capabilities, such as integrating multimedia files including video, photos, animations, and more. Therefore, you can utilize such multimedia components by simply activating JavaScript in your browsers. A website would be static without this, which is usually dull. 
  3. You will be missing out on a lot of current web development that is constantly enhancing user experiences if JavaScript isn’t enabled. 

The above points also state things that you’re going to miss if you have not enabled JavaScript in your web browser. 

How to enable JavaScript in your Browser?

Let’s start by learning how to activate JavaScript in your browser now that we’ve covered everything there is to know about it. 

For Google Chrome

Step 1: Go to Settings

Enable JavaScript in Chrome Browser

Step 2: Navigate to Privacy and Security

Enabling JavaScript in Chrome Browser

Step 3: Click on Site Settings 

Enabling JavaScript in Chrome Browser from Site Settings

Step 4: Click on JavaScript 

Click on JavaScript in Site Settings to Enable in-browser JavaScript for Chrome

Step 5: Click on Allowed. Also, you can mention specific sites to enable or disable JavaScript

Select the option to Enable JavaScript in Chrome Browser

For Firefox

Step 1: Enter ‘about:config’ in the URL bar of the firefox

Step 2: Search for the preference ‘javascript.enabled

Enable JavaScript in Firefox Browser

Step 3: Set the value to ‘true’ to enable JavaScript and ‘false’ to disable it

Enabling JavaScript in Firefox Browser

For Opera

Step 1: Go to Settings

Enabling JavaScript in Opera Browser

Step 2: Navigate to Privacy and Security and click on Site Settings

Open Site Settings to Enable JavaScript in Opera Browser

Step 3: Click on JavaScript 

Enable JavaScript in Opera Browser

Step 4: Click on Allowed. Also, you can mention specific sites to enable or disable JavaScript

Click on Allowed to Enable JavaScript in Opera Browser

For Microsoft Edge

Step 1: Go to Settings

Enable JavaScript in Microsoft Edge Browser

Step 2: Search for JavaScript and click on JavaScript

Enabling JavaScript in Microsoft Edge Browser

Step 3: Click on Allowed. Also, you can mention specific sites to enable or disable JavaScript

Click on Allowed to Enable JavaScript in Microsoft Edge Browser


It is worth noticing that JavaScript is such an important aspect of modern web development, that without it, a website becomes absolutely static and less interactive. A website that engages with users effectively stands out among the other websites on the internet. We also delved into the process of how JavaScript code is executed in the browser. 

Different web browsers have different JavaScript engines that are responsible for executing JavaScript and presenting it to the user. When JavaScript is disabled, a website’s user experience suffers; nevertheless, allowing JavaScript on an untrusted website might pose a security risk. We also discuss steps to enable JavaScript in different browsers. 

To test in-browser JavaScript it is necessary to test your website on real devices and browsers for better accuracy. BrowserStack Live allows you to test on 3000+ real devices and browsers for a comprehensive testing experience. You can perform tests under real user conditions like network simulation, geolocation testing etc.

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