HTML Viewer & Formatter Online
Preview and pretty-print HTML code live in your browser. Rendering is fully sandboxed.
Live rendering appears here as you type
How to use HTML Viewer & Formatter
- 1Paste, type, or load your HTML files and code into the editor.
- 2Click Preview to see a live rendering of your HTML CSS styling in the browser in real time.
- 3Switch to Formatted to auto-indent and pretty-print your HTML editor output.
- 4Copy the formatted output, or open HTML file previews directly.
Privacy & security
HTML rendering happens entirely inside an isolated <iframe> sandbox with no access to cookies, storage, or your network. This online viewer environment ensures nothing is sent to any server, making it a safe development environment.
Your HTML code never leaves your browser. No server requests are made when you paste, preview, or format HTML on this page.
Frequently asked questions
What is an HTML viewer?
An HTML viewer (also called an HTML previewer or renderer) lets you paste raw markup and instantly see how it renders in a browser. This tool helps you test and debug layouts without creating local files.
How does the online HTML viewer work?
Our online HTML viewer uses a secure, client-side sandbox iframe. When you paste your code and click Preview, the browser renders the output instantly. Since it runs 100% client-side, your code is never sent to any server.
Is there a difference between an HTML viewer online and an editor?
An editor lets you modify the source code, while a viewer renders the output. This tool functions as both: an interactive editor to write your code and an HTML viewer online to see the rendered result in real time.
Is this HTML online viewer free to use?
Yes, this HTML online viewer is completely free with no registration, no file size limits, and no installation required. You can load, format, and preview code templates instantly.
Can I use it to render HTML email templates?
Yes. Paste your HTML email markup, inline CSS, or template code, and preview exactly how the newsletter design renders. It is an excellent sandbox for developing responsive emails.
Live HTML Viewer & Tester
Using an Online HTML Viewer
An online html viewer is a valuable utility for developers, designers, and learners. It provides an instant rendering container to write, edit, and preview HTML and CSS code side-by-side without setting up local workspace files.
Interactive HTML Viewer Online
Using this html viewer online, you can paste code templates or draft layout sections to inspect how they display. The built-in parser formats raw markup, making it simpler to debug nested divs and tags in our sandboxed environment.
Key features of our free html online viewer
This html viewer features a sandboxed iframe to prevent script injections, an auto-formatting tool to clean up messy source code, and responsive viewing to test code styling in real-time.