JavaScript Playground
Write, run and debug JavaScript instantly in your browser — no setup required.
Ready to run
Press Run or Ctrl + Enter
Frequently Asked Questions
What is the JavaScript Playground?
It is a browser-based development environment that allows you to write, execute, and debug JavaScript code instantly without installing Node.js or any local development tools.
Does this JavaScript playground run code on a remote server?
No. All JavaScript code is executed entirely in your browser using the local JavaScript engine (V8 on Chrome, JavaScriptCore on Safari, etc.). Your code never leaves your computer, making it extremely fast and secure.
Can I use modern ES6+ features in this playground?
Yes. The playground supports all modern ECMAScript features supported by your browser, including async/await, promises, arrow functions, destructuring, and class syntax.
How do I view console outputs or print values?
You can use standard `console.log()`, `console.warn()`, or `console.error()` statements in your code. The playground intercepts these calls and displays them formatted inside the terminal panel.
Can I import external npm libraries?
This playground executes standard script blocks and does not support importing external npm packages directly via commonjs `require()` or esm `import` declarations. You should use client-friendly scripts or vanilla JS code.
Is it safe to paste and run sensitive JavaScript code here?
Yes, because the execution is 100% local. No data or code is sent to any backend servers. However, always exercise caution when running unverified third-party scripts.
How do I download my code?
Click the "Download" button to save your current playground session as a standard `.js` script file directly to your local computer.
What happens if my script has an infinite loop?
Since code executes on the browser's main thread, an infinite loop can temporarily freeze the page. If that happens, you can refresh the page to restart the environment.
Are there keyboard shortcuts to run the script?
Yes, you can run the code instantly at any time by pressing the `Ctrl + Enter` (or `Cmd + Enter` on macOS) keyboard shortcut.