Text Tools

XML Formatter

Validate and pretty-print XML with consistent indentation.

Error

DOMParser is not defined

Paste any XML and get a properly indented, validated version. The formatter checks for XML syntax errors and displays them clearly.

What is the XML Formatter?

An XML formatter is a code beautification tool that restructures XML documents with consistent indentation, proper nesting, and readable formatting. It parses the XML structure, removes unnecessary whitespace, and rebuilds the code with aligned elements so developers and data analysts can quickly understand document hierarchy without syntactic errors.

How it works

The tool reads your raw XML input, parses the document structure (tags, attributes, text nodes), and reconstructs it with configurable indentation (usually 2 or 4 spaces per nesting level). It detects and highlights syntax errors (unclosed tags, mismatched quotes, invalid characters) before formatting. You can choose between pretty-print mode (readable) or minify mode (compact), which removes all non-essential whitespace to reduce file size for transmission or storage.

Examples

InputResultNotes
<root><person><name>Alice</name><age>30</age></person></root><root> <person> <name>Alice</name> <age>30</age> </person> </root>Minified XML expanded with 2-space indentation, making nesting levels obvious and tags easy to locate.
<data><user id="1" active="true"><email>user@example.com</email></user><user id="2" active="false"><email>another@example.com</email></user></data><data> <user id="1" active="true"> <email>user@example.com</email> </user> <user id="2" active="false"> <email>another@example.com</email> </user> </data>Multiple records formatted with attributes preserved and clear visual grouping for rapid data navigation.
<svg><circle cx='50' cy='50' r='40' stroke='black' stroke-width='3' fill='red' /></svg><svg> <circle cx="50" cy="50" r="40" stroke="black" stroke-width="3" fill="red" /> </svg>Self-closing tags and attributes standardized; single quotes converted to double quotes per XML convention.

How to use the XML Formatter

  1. Paste or upload your XML code into the input field (raw, minified, or malformed).
  2. Select formatting preferences: indentation size (2 or 4 spaces), minify option, or validate-only mode.
  3. Click 'Format' to beautify the XML with proper structure and error detection.
  4. Review the formatted output and any error messages displayed at the top.
  5. Copy the clean XML by clicking the copy button or selecting all text.
  6. Paste into your editor, configuration file, API response handler, or database backup.

Benefits

  • Transforms unreadable minified XML into structured, hierarchical code that's easy to debug and review.
  • Detects syntax errors (unclosed tags, invalid attributes, malformed declarations) before they cause runtime failures.
  • Standardizes formatting across team workflows, ensuring consistent indentation and attribute quoting conventions.
  • Reduces file size when minifying XML for APIs, web services, or cloud transmission—typical reduction of 15–30%.
  • Saves hours of manual formatting for large XML documents with dozens or hundreds of nested elements.
  • No setup, no libraries to install, no API keys—works instantly in your browser with zero configuration.

Tips & common mistakes

Common mistakes

  • Assuming the formatter will fix structural logic errors—it beautifies and validates syntax, but won't reorder elements or change semantics.
  • Forgetting to preserve XML declarations (<?xml version="1.0" encoding="UTF-8"?>) when copying output; always check the top line.
  • Not checking for encoding mismatches—if your XML declares UTF-8 but contains non-ASCII characters, the parser may choke.
  • Minifying XML before confirming it parses correctly; invalid XML minifies too, silently compressing errors into production.

Tips

  • Use the minify option when embedding XML in URLs, JSON payloads, or database fields to save bandwidth and storage, but keep a formatted copy for debugging.
  • If the formatter reports unexpected errors, check for hidden characters, byte-order marks (BOM), or mixed line endings (CRLF vs LF) in your input.
  • Configure indentation to match your team's standard: most web APIs and configuration files expect 2 spaces; some legacy systems prefer 4.
  • For large XML files (>10 MB), test formatting on a small subset first to ensure the tool doesn't timeout or hang your browser.

Frequently asked questions

What is the difference between formatting and validating XML?

Formatting beautifies the structure with indentation and line breaks; validation checks that the XML is well-formed (all tags closed, attributes quoted, no invalid characters). This tool does both—it formats while validating, and reports errors if found.

Can I format XML that contains CDATA sections or comments?

Yes. The tool preserves CDATA blocks, comments, processing instructions, and DOCTYPE declarations unchanged, then applies indentation to surrounding elements. Your comments stay exactly as they are.

Does minifying XML remove my comments?

Standard minify preserves comments because they may contain important metadata or licensing info. If you want to strip comments entirely, check for a 'remove comments' option in the tool's advanced settings.

What happens if my XML has attributes with no values, like <input disabled>?

That's HTML syntax, not valid XML. In XML, every attribute must have a value: <input disabled="disabled" />. The formatter will flag this as an error and suggest the correction.

Can I format nested XML namespaces correctly?

Yes. The formatter respects namespace prefixes (e.g., <root xmlns:ns="http://example.com" /> and <ns:child />) and maintains them during beautification. Indentation applies to all elements regardless of namespace.

How do I know if the formatted output is safe to use in production?

If the formatter reports zero errors and the preview matches your original data content (only formatting changed), it's safe. Always test the formatted XML in your application with a small sample before deploying it to handle large files.

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FreeTooz Editorial Team · Last reviewed July 2026

Reviewed for accuracy. Results are estimates for general information and are not professional (medical, financial or legal) advice.