✦ Free Online JS Environment

Write JavaScript.
Run Your Ideas Instantly.

Write, edit and test JavaScript online with JS CODE OUTPUT. Experiment with functions, variables, logic and interactive web projects directly in your browser.

Open Main Editor ⚡ How It Works

script.js

// Create a simple greeting
function greetUser(name) {
  const message = "Hello, " + name + "!";
  console.log(message);
  return message;
}

const user = "Developer";
greetUser(user);

Console Output

❯ greetUser("Developer")
"Hello, Developer!"

✓ Code executed successfully.
No errors detected. Ready for your next idea...

A simple place to experiment with JavaScript

Learn, test and build JavaScript projects directly from your browser.

⚡

Write JavaScript Online

Write variables, functions, loops, conditions and other JavaScript code directly in your browser without any setup.

▶️

Run Your Code

Test your JavaScript ideas in real-time and inspect the exact output and errors from your code via built-in console.

🌐

Build Web Interactions

Combine JavaScript with HTML and CSS to create interactive frontend experiences directly on our main platform.

How to use the editor

Start experimenting with JavaScript in 3 simple steps.

Visit Main Site

Click on "Open Main Editor" to launch the full JS CODE OUTPUT workspace directly in your browser.

Write Your Code

Add logic, algorithms, or UI interactions using raw JavaScript inside the editor.

Live Preview & Test

Hit run and instantly see your outputs in the console or HTML preview window seamlessly.

Frequently Asked Questions

What is an online JavaScript editor?

An online JavaScript editor is a browser-based tool for writing, testing and experimenting with JavaScript code without needing to install local software like VS Code.

Is the JavaScript editor completely free?

Yes. JS CODE OUTPUT provides a completely free online JavaScript editing and testing experience for everyone.

Where can I access the full editor?

You can access our full fully-featured code editor by visiting our main website at js-code-output.vercel.app.

Ready to write some code?

Open JS CODE OUTPUT and start building incredible things.

Launch Editor Now →

Write JavaScript.Run Your Ideas Instantly.