Can I test JavaScript inside the HTML viewer?

Yes. You can include tags to test interactive DOM manipulations and animations inside a safe, sandboxed iframe environment.

Is my HTML code uploaded or stored on any server?

No. All editing and rendering is executed client-side in your browser. Your code remains private and is never logged.

Can I format messy or minified HTML code?

Yes. Click the 'Format source' button to automatically format and indent unorganized HTML markup.

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Developer Tools

Online HTML Viewer

Edit and render HTML safely in-browser with live preview.

Instant Results100% Client-Side Privacy100% Free Utility

Online HTML Viewer

Open or drop an HTML file, or paste markup, and see it rendered. Switch between the rendered page and its source, test device widths, or go full screen.

Files are read in your browser and never uploaded.

Drag and drop an .html file here, or

Or paste HTML

Relative links to local images or CSS files can't load in the viewer; use absolute URLs or inline them.

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About Online HTML Viewer

Open, drop or paste an HTML file to see it rendered in a secure sandbox, switch to the line-numbered source, test device widths, or view it full screen. Files never leave your browser.

Why Choose Our HTML Viewer

Feature	Smart Toolverse	Others
Live Split-Screen	Rendered and source views with device widths and full screen	Requires clicking a Run button
Sandbox Security	Isolated sandboxed iframe preventing script hijacking	Unsafe script execution
Beautify & Format	Built-in local HTML formatter	Plain unformatted textarea
Code Privacy	All code executes inside local browser memory	Saves code snippets to public databases

Common Uses & Applications

Test HTML email templates, experiment with CSS styles and Flexbox/Grid layouts, inspect raw webpage markup, and learn front-end web development with instant visual feedback.