Developer

HTML Viewer

A free online HTML, CSS, and JavaScript playground that runs entirely in your browser. Write code in tabbed editors, hit Run to see instant results in a sandboxed preview panel. Great for testing code snippets, prototyping UI ideas, debugging CSS, or learning front-end development. No server, no account, no data stored — everything stays on your device.

Preview

Features

codeTabbed HTML, CSS & JS editors
previewInstant live preview in sandbox
security100% client-side, no data stored
devicesResponsive — works on any device
speedNo build step, instant execution
restart_altOne-click reset to defaults

Frequently Asked Questions

What is the HTML Viewer?

The HTML Viewer is a free online code playground where you can write HTML, CSS, and JavaScript in separate tabbed editors and see a live preview of your code instantly — all inside your browser.

Is my code stored or sent to a server?

No. Everything runs 100% client-side in your browser. Your code never leaves your device — no server uploads, no cookies, no tracking.

Can I use JavaScript in the preview?

Yes. The preview runs in a sandboxed iframe with scripts enabled, so your JavaScript executes normally. DOM manipulation, event listeners, and console output all work as expected.

Is this a replacement for CodePen or JSFiddle?

It's a lightweight alternative for quick prototyping and testing. Unlike CodePen or JSFiddle, there's no account needed and no data is stored remotely. It's perfect for fast experiments and learning.

Does it support external libraries?

You can include external libraries by adding <script> or <link> tags directly in your HTML code. CDN links for popular libraries like React, Vue, or Bootstrap work out of the box.

Can I use it on mobile?

Yes. The interface is responsive and works on tablets and phones, though a desktop or laptop with a keyboard provides the best coding experience.

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