Introducing XML Formatter: Format, Minify & Validate XML Instantly

We built a free XML formatter. Paste your XML, click Format, get perfectly indented output in under a second. No login. No file upload. Everything runs in your browser.

→ xml-formatter.tools.jagodana.com

What Is an XML Formatter?

An XML formatter (also called an XML beautifier or XML pretty printer) takes compressed or inconsistently indented XML and reformats it with consistent indentation so it's easy to read.

Minified XML like this:

<?xml version="1.0"?><catalog><book id="bk101"><title>XML Guide</title><price>44.95</price></book></catalog>

Becomes this:

<?xml version="1.0"?>
<catalog>
  <book id="bk101">
    <title>XML Guide</title>
    <price>44.95</price>
  </book>
</catalog>

Same data. Completely readable.

Why Did We Build This?

XML is still everywhere — SOAP APIs, Maven pom.xml files, Spring configs, RSS feeds, SVG files, KML for mapping data, Android manifests, Microsoft Office document formats. Developers hit XML constantly.

But most existing formatters either send your XML to a server (problematic for credentials and PII), charge for "advanced" features, or are buried inside bloated multi-purpose tools.

We wanted a single-purpose tool that does one thing fast and never touches your data.

How Does the XML Formatter Work?

What technology does it use?

The formatter uses two built-in browser APIs that every modern browser ships with:

DOMParser — parses XML strings into a DOM tree and flags malformed XML with a <parsererror> element.

XMLSerializer — serializes the DOM tree back to an XML string, used for the minify operation.

For formatting (prettifying), we use a custom recursive node serializer that walks the DOM tree and rebuilds the XML string with configurable indentation. This approach handles all XML node types correctly:

• Element nodes — with attributes
• Text nodes — trimmed and inlined for leaf elements
• Comment nodes — <!-- preserved as-is -->
• CDATA sections — <![CDATA[...]]> preserved correctly
• Processing instructions — <?xml version="1.0"?> at the document level

What indentation options are available?

2-space and 4-space indentation. Switch with a single click. The indent setting persists across Format operations in the same session.

Can it validate XML?

Yes. Click Validate to check whether your XML is well-formed. The tool extracts the error message from the parsererror element and displays it in the status bar. Common errors caught:

• Unclosed tags
• Mismatched tag names
• Illegal characters outside CDATA
• Missing root element
• Multiple root elements

Is the XML Formatter Private?

Completely. Your XML never leaves your browser. There is no API call, no WebSocket, no server-side processing of any kind. The DOMParser and XMLSerializer APIs are built into the JavaScript runtime — they process data locally.

This makes the tool safe for:

• XML containing API keys or auth tokens
• Medical or financial data
• Proprietary configuration files
• Internal system exports

What Types of XML Does It Support?

The formatter handles any well-formed XML 1.0 document, including:

• Standard XML with nested elements and attributes
• XML with namespaces (xmlns:ns="...")
• XML declarations (<?xml version="1.0" encoding="UTF-8"?>)
• CDATA sections (<![CDATA[...]]>)
• XML comments (<!-- comment -->)
• Processing instructions (<?xml-stylesheet type="text/css" href="..."?>)
• Self-closing empty elements (<br/>, <meta/>)

Can It Handle Large XML Files?

Yes, with a caveat. Since all processing is in-browser, performance depends on device memory and CPU. Files up to a few megabytes format instantly on modern hardware. Very large files (10MB+) may take a few seconds. There is no hard file size limit imposed by the tool.

How Is This Different From Other XML Formatters?

| Feature | XML Formatter | Most Online Tools | |---|---|---| | Server upload | No | Yes | | Login required | No | Sometimes | | Validate XML | Yes | Sometimes | | Handles CDATA | Yes | Often broken | | Dark mode | Yes | Rarely | | Works offline | Yes | No | | Cost | Free | Free or freemium |

AEO Quick Answers

What is the fastest way to format XML online? Paste your XML into an online formatter and click Format. With XML Formatter by Jagodana, the output appears in under a second because all processing is local.

How do I pretty print XML in a browser? Use a tool like xml-formatter.tools.jagodana.com. Paste your XML, select your indent size, and click Format. No installation needed.

How do I validate XML without installing software? Use a browser-based XML validator. XML Formatter uses your browser's native DOMParser to check for well-formedness errors and displays the exact error message.

What is the difference between XML formatting and XML validation? Formatting changes the visual structure (indentation) without changing the data. Validation checks whether the XML is syntactically correct (well-formed). Both are available in XML Formatter.

Try it free: xml-formatter.tools.jagodana.com