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HTML/CSS/JS Code Playground

Prototype UI and scripts quickly with a simple in-browser sandbox. Live preview runs inside a sandboxed iframe.

HTML

CSS

JavaScript

Preview

Sandboxed iframe

How to use this tool

  1. Edit HTML, CSS, and JavaScript.
  2. Watch the preview update.
  3. Open the preview in a new tab if needed.

How to Use

Use the editors to modify HTML/CSS/JS and view output in the preview pane.

How It Works

Your code is injected into an iframe using srcDoc with a sandbox policy to keep execution isolated.

Key Features

  • Live preview
  • Sandboxed iframe
  • Open preview in new tab

Secure & Private

Everything runs locally. The preview is isolated in a sandboxed iframe.

Frequently Asked Questions

Is this like CodePen?
It’s a lightweight client-side sandbox for quick testing and prototyping.
Can it access my local files?
No. The iframe sandbox prevents direct file access.

Related Tools

HTML Playground

Edit HTML and preview it instantly in a sandboxed iframe.

CSS Playground

Edit CSS (and optional HTML) and preview it live.

JS Console Runner

Run JavaScript and capture console.log/info/warn/error output.

Privacy Notice

All processing happens inside your browser. No files or data are uploaded to our servers, ensuring your privacy is strongly protected.