DevToolKit

HTML Prettifier — Format Messy Markup Instantly [2026]

Paste minified or messy HTML → get clean, indented output in one click. Handles nested tags, void elements, and inline styles. Configurable indent size. 100% browser-based.

What is HTML Prettifier?

HTML Prettifier is a free online tool that formats and beautifies HTML code with proper indentation and structure. It takes messy, unindented, or minified HTML and transforms it into well-structured, readable code. This is useful for debugging, code review, and understanding HTML document structure.

How to Use HTML Prettifier

Paste your messy HTML code into the input area on the left. Select your preferred indentation size (2 or 4 spaces). The tool formats the HTML with proper indentation, handling nested elements, self-closing tags, and attributes. Copy the prettified HTML with one click.

How HTML Prettifier Works

The tool parses HTML by identifying tags, attributes, text content, and comments. It tracks the nesting depth and applies indentation accordingly. Self-closing tags (like <br>, <img>, <input>) do not increase the indentation level. Opening tags increase indent, closing tags decrease indent. The result is properly structured HTML that is easy to read and understand.

Common Use Cases

  • Formatting minified HTML for debugging and inspection
  • Beautifying HTML output from CMS or WYSIWYG editors
  • Making HTML templates readable for code review
  • Formatting HTML email templates for editing
  • Cleaning up HTML before adding it to documentation

Frequently Asked Questions

Does the prettifier change how the HTML renders?

In most cases, no. The prettifier adds whitespace for readability but does not change the HTML structure. However, in rare cases where whitespace is significant (e.g., inside <pre> tags), the formatting may affect rendering.

Can it handle self-closing tags like <br> and <img>?

Yes. The prettifier recognizes all standard HTML void elements (br, hr, img, input, meta, link, etc.) and handles them correctly without expecting closing tags.

What indentation sizes are available?

You can choose between 2 spaces and 4 spaces for indentation. The default is 2 spaces.

Is my HTML data sent to a server?

No. All formatting happens entirely in your browser using JavaScript. Your HTML code never leaves your machine.

Can it format HTML with inline CSS and JavaScript?

Yes. The prettifier handles HTML with inline styles and script tags. The HTML structure is formatted while the content inside style and script tags is preserved as-is.

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