Live collab is here. Invite your team

Code, run, share. In your browser.

A modern playground for HTML/CSS/JS, C# .NET, and SQL. Real-time collab over WebRTC. Cam, mic, screen-share, and instant code sync, built in.

Start a free pen Explore picks

Frontend, .NET, and SQL editors Live collaboration built in Free for public pens

/editor/frontend

Live

M A S

HTML

<!-- card.html -->
<article class="card">
  <h2>Hello, world</h2>
  <p>Welcome to CodeLabs.</p>
  <button id="go">
    Run me
  </button>
</article>

CSS

.card {
  background: #161c22;
  padding: 2rem;
  border-radius: 12px;
  color: #e6edf3;
}
button:hover {
  background: #007bc0;
}

PREVIEW

Hello, world

Welcome to CodeLabs.

// Three editors, one playground

Pick your stack. Press Run.

Frontend pens for the browser, backend snippets for .NET, and SQL queries. Every editor has the same collab fabric, the same shortcuts, the same look.

Frontend

HTML, CSS, JavaScript with preprocessors, autoprefixer, console capture, and live preview iframe sandbox.

HTML CSS / SCSS JS / TS React

.NET Fiddle

C#, VB.NET, F# in console, script, or full ASP.NET MVC mode. NuGet packages, real stdout, real exceptions.

C# VB.NET F# ASP.NET MVC

SQL Fiddle

SQLite today, MSSQL/MySQL/PostgreSQL coming soon. Format, analyze, export results to CSV.

SQLite MSSQL (soon) MySQL (soon) PG (soon)

// Real-time collaboration

Pair-program in the browser. No setup.

Cam, mic, screen-share, chat, and file transfer over LiveKit. Code, cursors, and project settings sync over SignalR. Everyone sees the same panels, the same mode, the same packages.

Cam, mic, screen share, recording

Code & cursor sync per editor

Chat + file shares in the dock

Project mode + packages stay in sync

3 connected

M A S

Try line 14, fontWeight should be 600.

good catch, fixing now

mock-data.json shared