Format & Beautify HTML Online — Free, Private, Client-Side
Paste messy or minified HTML and beautify it with clean, consistent indentation, then preview the result in a live iframe. This free online HTML formatter is a handy tool for developers cleaning up templates and markup — all in your browser.
Why this tool is useful
- Make minified or copied HTML readable again.
- Preview rendered output without saving a file.
- Catch unclosed tags while reformatting.
How it works (client-side)
- Paste your HTML into the input.
- Click Format to re-indent the markup.
- The live preview iframe renders the result locally.
Frequently asked questions
Does it fix broken HTML?
It re-indents existing tags but doesn't rewrite your markup logic; unclosed tags will still show in the preview.
Is the preview safe?
The preview runs in a sandboxed iframe in your browser; nothing is sent anywhere.
Is my HTML uploaded?
No — formatting and preview are entirely client-side.