HTML Beautifier

Format compact or messy HTML into readable, indented markup.

Input
Output
0 characters 0 lines

What does HTML Beautifier do?

HTML Beautifier formats HTML markup into readable indentation and nested tags.

  • Primary use: HTML Beautifier formats HTML markup into readable indentation and nested tags.
  • Key technical fact: HTML parsing follows browser rules from the HTML Standard, including error recovery for many malformed documents.
  • Practical check: Run the formatted or minified output through your parser, tests, or runtime when exact syntax behavior matters.
Topic Direct answer Source
Direct answer HTML Beautifier formats HTML markup into readable indentation and nested tags. WHATWG HTML Standard
Key fact HTML parsing follows browser rules from the HTML Standard, including error recovery for many malformed documents. WHATWG HTML Standard
Processing model Runs locally in the browser; no production Node server receives the input. Browser JavaScript

Make HTML easier to inspect and edit

HTML Beautifier expands compact HTML into a readable structure with line breaks and indentation around nested elements. It is useful for inspecting snippets, templates, generated markup, emails, and copied page fragments.

HTML parsers recover from many malformed documents, so beautified output can look cleaner than the source while still reflecting browser parsing rules. Formatting should preserve tags and attributes, but whitespace-sensitive inline text should be reviewed.

How to use

  1. Paste your HTML code into the input editor.
  2. Click Beautify HTML to reflow and indent the markup.
  3. Review the output for expected nesting, comments, inline text, and attributes.
  4. Use Copy for the clipboard, Download for a file, or Clear to reset.

What is HTML Beautifier?

HTML Beautifier is a browser-based utility for turning dense markup into a document you can scan and edit. It helps reveal parent-child relationships, misplaced closing tags, and large blocks of generated HTML.

HTML whitespace may affect inline layout, text nodes, and preformatted content. After beautifying templates or production markup, verify that rendered output still matches your intent.

Input notes

Paste HTML fragments or full documents. Be careful with <pre>, inline elements, templating syntax, and comments that your build system may rely on.

Example

A dense document becomes easier to follow once each nested element is placed on its own line:

--- Minified Input ---
<html><head><title>Test</title></head><body><p>Hello</p></body></html>

--- Beautified Output ---
<html>
  <head>
    <title>Test</title>
  </head>
  <body>
    <p>Hello</p>
  </body>
</html>

MCP integration

MCP (Model Context Protocol) lets AI agents and apps discover and run Coding.Tools utilities for repeatable conversions, formatting, hashing, and generation workflows.

MCP tool name: html-beautifier

MCP endpoint: https://coding.tools/mcp

Call tools/list first. Each tool entry includes inputSchema, outputSchema, and examples so an AI agent or client can build valid arguments without guessing.

For tools/call, read result.content[0].text for the display value and result.structuredContent for machine parsing. Tool-level failures return isError: true; protocol failures return a JSON-RPC error.

Example tools/call request:

curl -s https://coding.tools/mcp \
  -H "Content-Type: application/json" \
  -H "Accept: application/json" \
  -H "MCP-Protocol-Version: 2025-06-18" \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"html-beautifier","arguments":{"input":"<section><h1>Docs</h1><p>MCP ready</p></section>"}}}'

Most text and data tools accept an input string plus optional options. Browser-only image tools are listed for discovery and return a web UI link when they need browser image APIs.