When to use it
Previewing a UI snippet, a newsletter template, or user-submitted HTML and checking whether it still contains active scripts. A quick sanity check before pasting into production.
How it works
Paste HTML on the left and it renders on the right inside a sandboxed
iframe. An empty sandbox attribute means scripts never run and form
submissions are blocked.
Switch to Sanitized mode at the top to strip <script>, on* event
handlers, and javascript: / risky data: URLs. The cleaned markup
shows up in both the preview and the copy-ready output box. Raw mode
keeps the HTML untouched, but rendering still happens inside the
sandbox.
Limitations
<style>blocks are also removed — the sanitizer is tuned for email-style inline CSS rather than full stylesheets.- If you paste a full document (
<html>,<head>), only the<body>contents survive — a preview wrapper supplies its own chrome.
Where does your input go?
HTML parsing, preview, and sanitization all happen in your browser. Your markup is rendered inside a sandboxed iframe and never uploaded. Close the tab and it's gone.