Is the preview sandboxed?

Yes, it renders in an iframe with sandbox="allow-scripts" — scripts run, but the frame cannot access the parent page or navigate the top window.

Can I see console output from my JS?

Yes, console.log/warn/error/info calls inside the preview are captured and shown in the Console output panel.

How do I get a single shareable file?

Use the Download .html button, which inlines your CSS and JS into one self-contained HTML file.

Does the preview update automatically?

Yes by default, on a short debounce after you stop typing. Turn off Auto-run to use a manual Run button instead.

Is any of my code sent to a server?

No, everything is rendered and executed locally in your browser.

HTML Viewer with CSS & JS Tabs (Live Preview)

Edit HTML, CSS, and JS in tabs with an instant sandboxed live preview.

Support

Works Offline

Privacy First

No Login

No API

Editors

Write HTML, CSS and JS — the sandboxed preview reflects your changes.

Auto-run

HTML

Live preview

Rendered in a sandboxed iframe (scripts allowed, same-origin denied).

Console output

Captured console.log / warn / error calls from the preview.

No console output yet.

About the HTML Viewer with CSS & JS Tabs (Live Preview)

A three-pane HTML/CSS/JS playground: edit each in its own tab and watch a sandboxed iframe preview update on a short debounce (or run manually). Captures console.log/warn/error output from the preview into a panel, and lets you download the combined result as a single .html file or copy each tab individually.

Examples

Button click

<button id="btn">Click</button>

Output

console: Button clicked!

Keyboard shortcuts

Copy the main outputCtrl / ⌘ + Shift + C
Download the resultCtrl / ⌘ + S
Share this toolCtrl / ⌘ + Shift + S
Reset the inputsAlt + R
Open the tool search paletteCtrl / ⌘ + K

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Frequently asked questions

Version 1.0.0 · Updated 2026-08-11 · Runs entirely in your browser