JavaScript Compiler Online

Write, run, and compile JavaScript code instantly.

Run JavaScript online with TypeScript, JSX, and npm support. Compile JS code instantly in your browser. Free, no signup required. Trusted by 1.1M+ developers.

Open Compiler

Free · No signup required

1.1M+

Users

2.7M+

Projects Created

2016

Since

TRUSTED BY

New to JavaScript?

Start with these beginner-friendly tutorials

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About this tool

One of Playcode's coding tools

This compiler is one of the coding tools Playcode supports, free in your browser. Playcode's main product today helps you build and run websites and apps with AI: describe what you need, and the agent builds it, publishes it, and changes it when you ask. What is Playcode

Open AI Website Builder

Playcode's JavaScript Compiler

Trusted by over 1.1 million developers for compiling JavaScript online with instant execution

Learn JavaScript Online

The easiest way to learn JavaScript online. Compile JavaScript code instantly with no setup. Perfect for beginners, students, and coding bootcamps.

Run JavaScript online without downloads or configuration. This free online JavaScript compiler makes it easy to practice coding, follow tutorials, and see your code execute in real-time. Write JavaScript code, click Run, and see results instantly.

✓Instant compilation and execution
✓Helpful error messages for learning
✓Console output with execution time
✓Perfect for JavaScript online tutorials

Best JavaScript online compiler for: Students, coding bootcamps, JavaScript learners, online courses

Compile JavaScript with AI

AI-powered JavaScript compiler for professionals. Run JavaScript online with TypeScript, npm packages, and instant deployment. The fastest online JS compiler.

This online JavaScript compiler gives you professional-grade tools. Compile JavaScript online with full TypeScript support, JSX transpilation, and access to 2M+ npm packages. The best JavaScript online compiler for rapid prototyping and production development.

✓AI coding assistant (Pro feature)
✓Compile TypeScript, JSX, ES2026
✓Full npm ecosystem support
✓Hot module replacement (20-50ms)
✓Deploy to custom domains

Best for: Senior developers, rapid prototyping, MVPs, client demos, production apps

Team Collaboration

Compile JavaScript online together in real-time. Perfect for coding interviews, pair programming, and code reviews. Multiple developers can edit simultaneously.

Run JavaScript online with your team using real-time collaboration. This JavaScript compiler online supports live editing with multiple cursors, instant sync, and shared console output. The best online JS compiler for technical interviews and remote pair programming.

✓Real-time collaborative editing
✓Live cursors and selections
✓Share via URL instantly
✓Perfect for coding interviews

Best for: Technical interviews, pair programming, code reviews, teaching, remote teams

What is a JavaScript Compiler?

A JavaScript compiler transforms your source code into optimized, executable JavaScript online. Unlike traditional compilers, our online JavaScript compiler bundles your code, resolves imports, and transpiles modern syntax (ES2026, TypeScript, JSX) into browser-compatible code instantly.

Learn more: JavaScript Playground · TypeScript Playground · React Playground

Why Choose Playcode's JavaScript Compiler Online?

Lightning Fast Compilation

Compile JavaScript online in 20-50ms. Faster than local bundlers.

AI Coding Assistant

Write JavaScript online with AI that understands your code.

Full npm Support

Import 2M+ packages. React, Vue, Lodash, Axios.

One-Click Deploy

Publish compiled code to live URL with custom domains.

TypeScript & JSX

Compile TypeScript and JSX automatically.

Browser-Based

Run JavaScript online from any device, anywhere.

Use Cases for Online JavaScript Compilers

Learning & Practice

Learn JavaScript online without setup. Follow tutorials, compile JavaScript code, and see instant results.

Rapid Prototyping

Test ideas quickly. Import npm packages, build UI, compile JavaScript online in seconds.

Code Testing & Debugging

Run JavaScript online to debug algorithms and test code snippets with detailed console output.

Technical Interviews

Conduct live coding interviews. Compile JavaScript online with real-time collaboration.

Teaching & Education

Share JavaScript online examples via URL. Students can run JavaScript code without installing anything.

How to Use Our JavaScript Compiler

Write JavaScript Code Instantly. No setup, no installation required. Open your browser and start writing JavaScript, TypeScript, or JSX code immediately. Choose from pre-made templates or start from scratch.

Compile JavaScript in Real-Time. Our JavaScript compiler processes your code instantly as you type. See compilation results immediately with zero delay. No build step, no waiting.

Debug with Powerful Console. Our JavaScript compiler includes a professional console for debugging. See console.log outputs, errors, and warnings instantly. Track execution time and catch bugs quickly.

Compile TypeScript & JSX. Our JavaScript compiler supports TypeScript, JSX, and TSX out of the box. Write modern code with full type checking and React components. No configuration needed.

          
            // TypeScript with type checking
interface User {
  name: string;
  age: number;
}

          
            // JSX with React components
const App = () => (
  <div>Hello, World!</div>
);

// Compiled successfully in 23ms

Publish Your Compiled Code. Deploy your JavaScript project to a live URL with one click. No server setup, no hosting configuration. Connect custom domains and share your compiled code with the world.

Publish JavaScript compiler projects to live URL — Deploy and publish compiled JavaScript code to a live website with custom domain

Features

Code Autocomplete. Enhance your coding speed and efficiency with smart code autocomplete feature. Avoid checking the documentation frequently.

Bug Finder. Playcode can identify and display all errors, providing assistance to fix them. Write, run code, correct any errors quickly.

The Most Flexible Layout.

Arrange panels as you like.

Upload Assets. Images, videos, sounds, shaders and others.

Color Themes.

Feels great in any environment.

Ready to use
JavaScript Playground

No need to configure your own IDE preset, start immediately.

Open Playground

Code seamlessly from any device

Jumping from your Mac to your iPad to your iPhone is no problem. Web editor is optimized for all devices.

Frequently Asked Questions

What is a JavaScript compiler?

A JavaScript compiler transforms your JavaScript code into optimized, executable code. Unlike traditional compilers that produce machine code, online compilers like this one bundle your code, resolve imports, and transpile modern syntax (ES2026, TypeScript, JSX) into browser-compatible JavaScript that runs instantly.

Is Playcode's JavaScript compiler free?

Yes. The JavaScript compiler is a free browser-based coding tool: compile and run JavaScript, use npm packages, and see the live preview without paying. It is one of Playcode's supported coding tools. Playcode's main product, the AI builder that creates and runs websites and apps, is separate: it uses AI credits, with trial credits included and paid plans for more.

Can I use npm packages in the online compiler?

Yes. Import any npm package, such as React, Vue, Lodash, or Axios, and the compiler fetches and bundles it automatically. No npm install needed. Popular packages are cached, so repeat imports load fast.

How does the AI coding assistant help?

Every Playcode project includes the AI agent. In the compiler it can write code, fix bugs, explain errors, and help you learn JavaScript: describe what you want, and it generates working code across multiple files. AI work uses credits; trial credits are included to start.

Does the JavaScript compiler work offline?

The compiler keeps working offline once the page is loaded. It runs entirely in your browser using WebAssembly, so you can keep coding without an internet connection. Your code is saved locally and syncs when you're back online.

What languages does the compiler support?

The compiler handles JavaScript (ES2026), TypeScript, JSX, TSX, and CSS. You can build React, Vue, Svelte, and vanilla JS projects. Transpilation is automatic, so you write modern code and it runs in any browser.

How fast is the online JavaScript compiler?

The compiler is optimized for speed. Initial compilation takes 100-500ms depending on project size. Incremental builds (when you edit code) complete in 20-50ms. That's often faster than running a local Node.js bundler because everything runs in memory with no disk I/O.

Can I publish my project to a live website?

Yes. Publish your project to a live URL with one click. No deployment setup, no hosting provider, no server configuration: hosting, SSL certificates, and CDN are included. Custom domains are available on paid plans.

Does Playcode support real-time collaboration?

Yes. Collaborators can edit the same project at the same time and see each other's changes live. Everything is auto-saved to the cloud, so you do not lose your work. The number of collaborators depends on your plan.

What our users value

No coding needed

Results in minutes

Works on phone

Best online JavaScript compiler

I've tried every online JS compiler out there. Playcode is the only one that actually feels like a real IDE. The Monaco editor, instant preview, and npm support make it perfect for quick prototyping.

- Alex Chen, Frontend Developer