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HTML Viewer

Paste HTML, CSS and JavaScript. See the page live on phone, tablet and desktop.

Private: your code stays in your browser.

HTML code26 lines
Press Run to see your code.
Console
Nothing logged yet. console.log() and errors from your code show here.

How it works

  1. 1Paste your HTML, or pick an example. Include your CSS and scripts in the same file.
  2. 2The preview updates as you type. Switch the width to check mobile and tablet.
  3. 3Read the console for errors, then copy a share link or download the page.

Questions

Can I use CSS and JavaScript?

Yes. Put them in style and script tags in the same HTML. Scripts and stylesheets from https addresses, such as a Tailwind or Chart.js CDN, load too.

Why are alert() and pop-ups blocked?

The preview is sandboxed for safety. Use console.log() and the Console panel under the preview instead.

Can the page use my cookies or log in to my accounts?

No. The preview has no access to this website or its cookies.

Is it safe to run code I did not write?

Your code runs in a locked box (a sandboxed frame) with no access to this website, its cookies or your accounts, and it cannot open pop-ups or send you to another page. Even so, only run code you trust, because it can still draw on the screen and make network requests.

Is my code uploaded?

No. It is read and run in your browser, and the share link keeps the code after the # sign, which a browser never sends to any server.

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About the HTML Viewer

The HTML Viewer previews HTML, CSS and JavaScript live in your browser. Paste code and see the page instantly.

When to use it

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