HTML Viewer

Paste HTML or open a .html file and see it drawn at once — in a sealed preview that cannot touch this site.

Scripts are off. Tick Run scripts and the page’s JavaScript runs inside a sealed box: it cannot read this site’s saved data or cookies, open windows or submit forms. It can still load images from the web.

The preview is sealed: links inside it do not take you anywhere, and an image, stylesheet or font loaded from a web address shows up while a script, video or request from another site does not.

🔒 Runs entirely in your browser — nothing you type is uploaded or stored on a server.

Paste HTML — a snippet, an email template, a whole page — or open a .html file, and it is drawn right below as you type. Switch between Full, Tablet 768 and Phone 375 to see how the layout responds: the page inside the preview sees the preview’s width, so its media queries really do switch.

Also on Txtset: strip the tags and keep the text · write Markdown and get the HTML.

The preview is sealed. Your HTML is drawn in a sandboxed frame with no way into this site. It cannot read what you have saved here (Notepad text, AI chats, a Secret Santa draw), cannot read cookies, cannot open windows, submit forms or send this tab somewhere else. Scripts are off until you tick Run scripts, and even then they run in the same sealed box, so a script that reaches for this site’s storage gets an error instead of an answer.

Images, stylesheets and fonts loaded from https:// addresses do show up, so a page that links its CSS or a web font looks the way it would in a browser. Scripts from other websites, video and audio do not load, and neither does anything referred to by a relative path such as logo.png — a pasted snippet has no folder next to it, so use a full address.

Nothing is uploaded, and there is deliberately no “open in a new tab” button. A new tab opened from this page would run your HTML as part of txtset.com, with access to everything this site stores. Download .html is the way out: opened from your disk, the file gets an origin of its own. The line above the preview shows the element count, the page title and the size, so you can see at a glance that the page was read.

How to use

  1. Paste your HTML into the box, or press Open .html file and choose one. The preview updates about a third of a second after you stop typing.
  2. Pick Full, Tablet 768 or Phone 375 to see the page at that width.
  3. Tick Run scripts only if the page needs JavaScript to show anything. It stays sealed either way.
  4. Read the line above the preview for the element count, the title and the size, and press Download .html to save the page as a file.

Examples

<h1>Hello</h1>
A bare snippet is drawn at once. With no <!doctype html> the preview is in quirks mode, as a browser opening that file would be.
A page with <link rel="stylesheet" href="https://…">
The stylesheet loads from its address and the page is styled.
<script>document.body.textContent = "hi"</script> with Run scripts ticked
The script runs and rewrites the body, inside the preview only.
The same script with Run scripts unticked
Nothing runs. The page is shown as inert markup.

Frequently asked questions

Is it safe to paste HTML from someone I do not trust?
Safer than opening the file, but not a licence to be careless. The preview is a sandboxed frame that is not treated as part of txtset.com, so it cannot read this site’s storage or cookies, navigate your tab, open windows or submit forms, and scripts are off unless you turn them on. With Run scripts ticked, a script can still draw anything it likes in its box and ask the web for images — including your keystrokes if you type into its fields. Never type anything real into a preview of a page you did not write.
Why does a script from another website never load?
Because this page lets the preview fetch images, stylesheets and fonts from the web but not scripts. The site’s security policy refuses a <script src> from an ordinary website, so nothing from outside can run beside your HTML; the browser’s console reports the block. Scripts written out inside your HTML run when you tick Run scripts.
Why is there no &ldquo;open in a new tab&rdquo; button?
A link to a new tab made by this page would have this page’s origin, so the HTML you pasted would run there with no sandbox and could read everything this site keeps in your browser. Download .html hands you a file instead; opened from disk, it is an ordinary local page with an origin of its own.
Is anything uploaded?
No. The HTML you paste or open stays in this tab, which is why there is no share link. Images, stylesheets and fonts the page points at are fetched by your browser from the sites that host them, exactly as if you had opened the page, but the HTML itself is never sent.
Why does my page look different from the real thing?
Usually one of four reasons. A relative path such as images/photo.jpg has no folder to point into. With no <!doctype html> the preview is in quirks mode. A <meta name="viewport"> tag has no effect inside a frame, so use the width presets instead. And scripts are off until you tick Run scripts.
Can I preview an HTML email?
Yes. Paste the source and read it at Phone 375. Mail apps rewrite or strip some HTML and CSS before showing a message, so treat this as a check of your markup, not a promise of how every inbox will draw it.
How big a page can it show?
Up to 2 MB of HTML, pasted or opened. Past that the page says so instead of freezing.

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