How can I encrypt/protect JavaScript source code

JavaScript is the most popular web programming language that comes with a lot of useful features. One of these features is immediate parsing i.e the browser executes the code as it downloads the content. This makes it browser interpreted or client side programming language. Therefore, it works on the client machine and hence making it difficult to hide the code from the client.

Immediate parsing has its perks but it also comes with major downsides. As the source code is easily visible, everyone can read it. This can cause major security risks and hence the code needs to be protected.

Sometimes you want to protect your JavaScript code from hackers, and sometimes you want to showcase an application but at the same time you don’t want your code to be copied. In this article, we’ll learn how to protect your JavaScript code and decrease the security risk.

Protect JavaScript Code

Since you can’t hide your code but you can make it difficult to read for the user. But, if your code is easily readable and understandable to the user, the chances of your code being copied will be high. So, for this a number of techniques are used to alter your code without changing the functionality. The two most popular ways are:

  • Obfuscate
  • Minify

First we will see what obfuscation is and tools available for it.

What is Obfuscation

Obfuscation is the technique of going through your source code, changing the variables and rearranging them, breaking the application logic and hiding the original algorithm.

An obfuscated code is difficult to understand and hence decreasing the security risk. Although the code can be deobfuscated, it’ll leave users with meaningless variables and hard to understand logic, with no comments, making it useless on large scale projects.

There are various JavaScript obfuscator tools available online. Some of the best ones are listed down below:

  • JavaScript Obfuscator
  • UglifyJs
  • Jscrambler

Let’s look at them one by one, and the features they provide:

JavaScript Obfuscator

JavaScript Obfuscator comes with various functionality, from compressing the code, altering the flow to breaking the program’s logic and hiding the original algorithm. Furthermore, it confuses the user by applying dead/useless code that is not runnable and hence causing confusion to the reader.


Another tool available for this purpose is Uglify, that makes the program “unintelligent” without altering the functionality. Goal is to make it unreadable by compressing and renaming the variables and functions. It’s also irreversible.


Jscrambler increases the security of your code by adding various protecting layers like code locks and self-defending capabilities. Thus, making it unreadable for any stealer or hacker.

What is minify

Minify, also known as minification, is simply compressing your code in such a way that it removes all unnecessary characters without changing the functionality. These characters include white spaces, comments, unnecessary parenthesis or variable declaration etc. This makes the code difficult to understand and hence decreasing the risk of being copied.

There are several tools as well to perform this task, some of which are:

  • Javascript compression tool
  • Minify your JavaScript

Javascript compression tool

Javascript compression tool is available to compress your code by removing all unnecessary characters, comments, reducing its size and hence making it difficult to understand for the client.

Minify your JavaScript

This Javascript Minifer is available providing the same functionality. Users can upload their code and generate a minified version of it. Furthermore, users can download the generated file of their source code as well.


Protection of code is an important aspect in JavaScript. In this article we saw why encryption or protection of your code is extremely important, the risk that comes with JavaScript and ways to reduce those risks. The main task for JavaScript developers is always protecting their source code and for this purpose various ways are available. It’s better to protect your code through various tools and technologies rather than leaving it unprotected and increasing security risks. Hence, tackling this issue beforehand will always put you ahead of the attackers and stealers.

About the author

Shehroz Azam

A Javascript Developer & Linux enthusiast with 4 years of industrial experience and proven know-how to combine creative and usability viewpoints resulting in world-class web applications. I have experience working with Vue, React & Node.js & currently working on article writing and video creation.