JavaScript Online Compiler
Last Updated :
05 May, 2025
The JavaScript (JS) Online Compiler and Editor is a free online tool providing an integrated development environment (IDE) for creating and executing JavaScript code. Whether you are a beginner looking to learn JavaScript or an experienced developer want to test snippets of code quickly, an online compiler is an essential tool. An online JavaScript compiler allows you to write, run, and test JavaScript code instantly without the need for setting up any local environment.
In this article, we will explore some popular online JavaScript compilers and why using an integrated online development environment (IDE).

JavaScript online compiler offers a platform for writing, compiling, and debugging the code. This Code Editor provides various features, like light and dark mode, copy code, reset, fullscreen mode, code formatting, run code, and generating URLs for sharing.
Why Use a JavaScript Online Compiler?
Online compilers and IDEs provide several advantages:
- No Setup Required: No need to install JavaScript compilers or configure environments locally. Just open the browser and start coding.
- Cross-Platform: Since these tools run in the cloud, they are platform-independent. Whether you're on Windows, macOS, or Linux, you can access the same interface.
- Quick Prototyping: Great for testing small code snippets, debugging, and experimenting with new concepts quickly.
- Collaboration: Many online compilers provide features for code sharing and real-time collaboration with teammates or communities.
- Educational Tools: Beginners can start learning JavaScript interactively, without dealing with any initial setup issues.
Popular Online JavaScript Compilers
Here are some well-known JavaScript online compilers and IDEs:
1. GeeksforGeeks JavaScript IDE
The GeeksforGeeks JavaScript IDE and HTML, CSS, and JavaScript code editors are excellent choice for developers looking for an integrated platform to write, test, and run JavaScript code. It is specifically designed to help learners and professionals improve their coding skills through practice.
Key Features
- Option to execute only JavaScript code.
- Write JavaScript, HTML, and CSS in separate panes.
- Real-time code execution.
2. JSFiddle
JSFiddle is one of the most widely used online editors for web development. It allows you to write JavaScript, HTML, and CSS together in a single environment and provides live previews of your code.
Key Features
- Write JavaScript, HTML, and CSS in separate panes.
- Integrates popular JavaScript libraries.
- Real-time code execution.
3. CodePen
CodePen is a social development platform designed for front-end designers and developers. It is a popular choice for sharing JavaScript demos, web animations, and creating interactive visualizations.
Key Features
- Live previews.
- Support for JavaScript, HTML, and CSS.
- Large community and easy sharing of "Pens" (code snippets).
Example: This example illustrates the JavaScript code inside an HTML file using a script tag for finding the sum of the two numbers.
Online JavaScript Compiler (Code Editor) Features
- Light and Dark Mode: The code editor features both light and dark modes, allowing you to switch between them with ease.
- Shortcuts: The code editor has the feature of Keyboard shortcuts there are various shortcuts that help you to write code faster.
- Reset: With, this feature you can reset your page without refreshing the page.
- Copy Code: This is a feature that lets the user copy their code and they can paste it anywhere they want.
- FullScreen Mode: In this feature, you can code on full screen and exit by pressing the ESC key.
- Format: This feature gives proper formatting of the code which helps the user to understand quickly and code look presentable.
- Run: With this feature, you can easily run your code on the same page so you don't need to jump from one page to another which helps to debug code easily will less distraction.
- Run+Generate URL: This is a powerful feature that provides you the feature to run code and gives you a URL with a one-click through which you can showcase your website project to anyone.
Similar Reads
HTML Online Compiler
The HTML Online Compiler is an online integrated development environment (IDE), supporting the creation of different software applications. It is a platform for coding, compiling, and debugging, formatting to improve the efficiency of the development process. This Code Editor provides various featur
2 min read
Uses of JavaScript
JavaScript is a versatile programming language extensively used in web development. It empowers interactive features like form validation, dynamic content updates, and user interface enhancements. Furthermore, it's employed in server-side scripting, mobile app development, game development, and even
3 min read
Introduction to JavaScript
JavaScript is a versatile, dynamically typed programming language used for interactive web applications, supporting both client-side and server-side development, and integrating seamlessly with HTML, CSS, and a rich standard library.JavaScript is a single-threaded language that executes one task at
7 min read
Embedding an online compiler into a website
How to add a JDoodle compiler into a website?Using the JDoodle compiler we can write our code in C, C++, Java, and in many more programming languages, and then we can embed and easily run that program in our webpage by giving standard inputs, and we can give command line arguments also.Steps to foll
2 min read
HTML DOM Navigator javaEnabled( ) Method
The navigator javaEnabled() method is used for returning a Boolean value that specifies whether Java is enabled in a browser or not. It returns true if Java is enabled in the browser else it returns false. Syntax: navigator.javaEnabled()Note: This method has been deprecated and is no longer used. Re
1 min read
How to write programs in your website and redirect it in JDoodle online compiler ?
There may be situations where it may be required to run a piece of code that has been entered by the user. This can be done by using JDoodle. We can write our programs in any programming language on our website page and it can be redirected to the JDoodle online compiler to be run on that website.No
2 min read
How To Execute HTML Program?
HTML (HyperText Markup Language) is the standard language used to create web pages. Executing an HTML program is the process of rendering the code in the browser to display a web page. There are several approaches to running HTML code each suitable for the different environments and use cases. we wi
2 min read
Top 10 Free Online IDE, Compilers in 2025
In the era of cloud computing, isn't it so boring to use the old-school offline compilers and IDES? No doubt the offline are brilliant, but we have to install different compilers for each language manually on every system physically, which requires a lot of space, and also it is not easy to carry th
9 min read
10 Best Java Compilers in 2025
Java Compilers refers to a program that takes the text file work of a software developer and compiles it into a platform-independent Java file. The Java compilers mainly include the Java Programming language compilers (javac), the Eclipse compiler for Java(ECJ), the GNU, and Jikes. The Java Compiler
7 min read
Online Code Compiler and Judging System | Source Code, UML diagrams, Project Report
Online Code Compiler and Judging System is one of the most common software development projects today. In this article, we are going to develop the Online Code Compiler and Judging System software development project from scratch for final year students. We will be covering all the steps you need to
15+ min read