Skip to main content
UFOZoo

XML Formatter: Beautify, Validate & Minify XML Online

XML formatter online: beautify, validate, and minify XML with indentation control, error line reporting, and online validation.

Updated 2026-08-16

Related Tools

JSON Formatter: Beautify, Validate & Minify JSON Online

SQL Formatter: MySQL, PostgreSQL & SQL Server Beautifier

YAML to JSON: Convert Docker/K8s Config Files Online

XML to JSON Converter: XML Files to JSON Instantly

Code Beautifier: Format HTML, CSS & JavaScript Online

Code Minifier: Minify HTML, CSS & JavaScript Online

Features

  • Real-time XML formatting as you type: paste and it formats instantly with proper indentation and line breaks
  • Custom indentation options: choose between 2 spaces, 4 spaces, or tab characters to match your coding style
  • Syntax highlighting with color-coded tags (blue), attributes (amber), strings (green), comments (gray), CDATA sections (purple), and processing instructions (orange)
  • One-click minification for production: remove all unnecessary whitespace to reduce file size significantly
  • XML validation with error detection: identify syntax errors with precise line and column positioning
  • Support for XML comments, CDATA sections, processing instructions, and complex nested structures
  • Drag-and-drop files: simply drag .xml files into the input area or use the open button
  • One-click copy to clipboard or save as .xml file; formatted or minified versions available
  • Works offline after first load

How to Use

  1. 1Paste your XML document into the left editor area; it will format automatically as you type
  2. 2Choose your preferred indentation style: 2 spaces, 4 spaces, or tab from the toolbar options
  3. 3Switch between 'Formatted' and 'Minified' tabs to view either beautified or compressed output
  4. 4Use the Copy button to copy the result to clipboard, or Download to save it as an .xml file
  5. 5Drag and drop a .xml file onto the input area to load it instantly instead of pasting
  6. 6When validation errors occur, look for the error indicator near the line number; the error message shows the approximate line and column
  7. 7Use the Upload button to open an XML file from your device's file picker
  8. 8Compare formatted vs minified versions side by side to understand what whitespace was removed

Frequently Asked Questions

Why is my XML all on one line?

Because the file was minified, saved without indentation or line breaks to save space. XML formatting (also called beautifying or pretty-printing) adds proper indentation, line breaks, and spacing back, so the document's nesting structure becomes clearly readable. Paste the one-line XML here and it is formatted instantly.

How does XML minification work?

XML minification removes all unnecessary whitespace including indentation, line breaks, and extra spaces between tags while preserving the document's semantic meaning. This reduces file size significantly, making it ideal for production environments where bandwidth matters.

Does this tool support XML validation?

Yes! The formatter performs basic XML syntax validation and will highlight any errors found in your document, showing the error message along with the approximate line number where the issue was detected.

Can I use this tool for large XML files?

Yes, the tool can handle large XML files efficiently since all processing happens in your browser. However, extremely large files (10MB+) may experience slower performance due to browser memory limitations.

How do I format XML in Notepad++?

Notepad++ has no built-in XML formatting. Install the XML Tools plugin (Plugins Admin → search 'XML Tools'), then use Ctrl+Alt+Shift+B to pretty print and Ctrl+Alt+Shift+M to minify. Alternatively, paste the XML into this web tool; same result with validation, indentation choices, and no installation.

How do I format XML in VS Code?

VS Code formats XML with Shift+Alt+F (or right-click → Format Document); installing the Prettier extension keeps XML/JSON formatting consistent. Those work well for files you already have open; for a quick one-off paste, this web tool gives the same formatted output in the browser.

What XML features are supported?

The formatter supports all standard XML features including: elements and attributes, comments (<!-- -->), CDATA sections (<![CDATA[...]]>), processing instructions (<?xml ...?>), namespaces, nested structures, self-closing tags, and special character entities.

Can I customize the indentation style?

Yes! You can choose between 2-space indentation, 4-space indentation, or tab characters. Select your preferred style from the toolbar options in the formatted view to match your project's coding standards.

How do I save the formatted XML?

Click the save button in the output toolbar to save the formatted or minified XML as a .xml file. Alternatively, use the copy button to copy the result to your clipboard and paste it into your editor.

Why would I need to format XML?

Formatted XML is essential for debugging configuration files (web.config, pom.xml), working with SOAP/REST APIs, editing SVG graphics, processing RSS feeds, validating sitemaps, and collaborating with team members who need to read and modify XML documents.

How do I know if my XML has errors?

The validator checks for: unmatched tags (each opening tag needs a matching closing tag), improper nesting, invalid characters in attribute values (like unescaped &), missing quotes around attribute values, and malformed comments or CDATA sections. Errors are shown with the approximate line number; look for the red error indicator next to the line numbers.

Why does my xml formatter show an error for a file that opens fine in my browser?

Browsers are lenient: they render malformed XML with recovery (and Firefox even shows a warning instead of blocking), while a strict parser reports it. The usual strictness gaps: multiple root elements, unquoted attribute values, unclosed or mis-nested tags, and raw & or < in text instead of &amp;/&lt;. The error line number points at the first problem; fix those and the same file that 'worked' in the browser will format cleanly.

Why does my xml formatter online free reformat differently than my IDE?

Different formatters use different defaults: 2 vs 4 spaces vs tabs, whether attributes are wrapped to new lines, how empty elements are written (<a/> vs <a></a>), and whether the XML declaration stays on line one. Both outputs are valid, well-formed XML; the differences are cosmetic. This tool lets you choose indentation, so match the project's existing style; the same XML parses identically no matter which formatting you pick.