Format XML
What Is an XML Formatter?
An XML formatter is a tool that takes unformatted or minified XML and adds proper indentation so you can see the document's hierarchy. This formatter also validates your XML structure and reports syntax errors like unclosed tags or mismatched nesting.
How to Use This Tool
- Paste your XML into the input panel on the left
- Choose indentation — click "Format (2 spaces)", "Format (4 spaces)", or "Format (tabs)"
- Review the output — formatted XML appears in the right panel
- Copy or download — use the buttons above the output panel
To reduce file size, click Minify to remove all unnecessary whitespace.
Example
Input (minified):
<catalog><book id="1"><title>XML Guide</title><price>29.99</price></book><book id="2"><title>Data Formats</title><price>19.99</price></book></catalog>Output (formatted with 2 spaces):
<catalog>
<book id="1">
<title>XML Guide</title>
<price>29.99</price>
</book>
<book id="2">
<title>Data Formats</title>
<price>19.99</price>
</book>
</catalog>Features
- Pretty print with customizable indentation (2 spaces, 4 spaces, or tabs)
- Minify to remove all whitespace between tags
- Validate XML structure and report parse errors
- Copy or download formatted output
- Live stats — line count and file size displayed in real time
- Client-side only — your XML never leaves your browser
When to Format vs Minify
- Format when debugging, reviewing, or documenting XML — indentation reveals structure and makes unclosed tags obvious
- Minify when reducing payload size for APIs, configuration deployment, or storage
Frequently Asked Questions
Does formatting change the meaning of XML?
No. Adding or removing whitespace between tags does not change the data. XML parsers treat indentation as insignificant whitespace. Minified and formatted versions are semantically identical.
Is my XML data sent to a server?
No. All formatting, validation, and minification happens in your browser using JavaScript. Your XML data never leaves your device.
What does "Invalid XML" mean?
The parser found a syntax error -- usually an unclosed tag, mismatched nesting, unescaped special characters (<, &), or unquoted attribute values. The status bar shows the first error found.
Should I use 2 spaces, 4 spaces, or tabs?
It depends on your project conventions. Two spaces are compact and common in web development. Four spaces give more visual separation. Tabs let each developer set their preferred width. The choice does not affect parsing.
Can I format very large XML files?
This tool runs in your browser, so performance depends on your device. Files up to a few megabytes format quickly. For very large files (50MB+), a command-line tool like xmllint may be more practical.
What is the difference between formatting and validation?
Formatting adds indentation for readability. Validation checks whether the XML follows syntax rules (well-formedness). This tool does both -- it validates the structure while formatting the output.
What is the difference between XML and HTML formatting?
XML is strict -- every tag must be closed and attributes must be quoted. HTML is more lenient and allows unclosed tags like <br> and <img>. An XML formatter will reject HTML that is not valid XHTML.
When should I minify XML instead of formatting it?
Minify XML when reducing payload size for APIs, configuration deployment, or storage. Format XML when debugging, reviewing, or documenting -- indentation reveals structure and makes unclosed tags obvious.
Related Resources
- XML to JSON Converter — convert XML data to JSON format
- JSON to XML Converter — convert JSON back to XML
- JSON Formatter — format and validate JSON data
- HTML Formatter — format HTML with proper indentation
- XML Formatting Explained — learn XML syntax, structure, and common mistakes
Privacy & Limitations
- All calculations run entirely in your browser -- nothing is sent to any server.
- Results are computed locally and should be verified for critical applications.
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XML Formatter FAQ
Does formatting change the meaning of XML?
No. Adding or removing whitespace between tags does not change the data. XML parsers treat indentation as insignificant whitespace. Minified and formatted versions are semantically identical.
Is my XML data sent to a server?
No. All formatting, validation, and minification happens in your browser using JavaScript. Your XML data never leaves your device.
What does Invalid XML mean?
The parser found a syntax error -- usually an unclosed tag, mismatched nesting, unescaped special characters, or unquoted attribute values. The status bar shows the first error found.
Should I use 2 spaces, 4 spaces, or tabs for XML indentation?
It depends on your project conventions. Two spaces are compact and common in web development. Four spaces give more visual separation. Tabs let each developer set their preferred width. The choice does not affect parsing.
Can I format very large XML files in the browser?
This tool runs in your browser, so performance depends on your device. Files up to a few megabytes format quickly. For very large files (50MB+), a command-line tool like xmllint may be more practical.
What is the difference between XML formatting and validation?
Formatting adds indentation for readability. Validation checks whether the XML follows syntax rules (well-formedness). This tool does both -- it validates the structure while formatting the output.
What is the difference between XML and HTML formatting?
XML is strict -- every tag must be closed and attributes must be quoted. HTML is more lenient and allows unclosed tags like br and img. An XML formatter will reject HTML that is not valid XHTML.
When should I minify XML instead of formatting it?
Minify XML when reducing payload size for APIs, configuration deployment, or storage. Format XML when debugging, reviewing, or documenting -- indentation reveals structure and makes unclosed tags obvious.