XML Formatter & Validator

About XML Formatter & Validator

The XML Formatter & Validator uses the browser's built-in DOMParser to parse your XML, check it for well-formedness errors, and re-serialize it with consistent 2-space indentation and syntax-highlighted output. It also reports element count, attribute count, and maximum nesting depth so you can understand the shape of your document at a glance.

Whether you're working with RSS feeds, SOAP envelopes, Maven POMs, or Android resource files, this tool helps you quickly spot structural problems. All parsing is performed locally — your XML content is never transmitted to a server.

Common Use Cases

• Formatting minified or single-line XML API responses (e.g., SOAP, XML-RPC) for human inspection
• Validating well-formedness of Maven pom.xml, Android AndroidManifest.xml, or Spring configuration files
• Checking RSS and Atom feed documents for unclosed tags or missing namespace declarations before publishing
• Minifying XML config files to reduce payload size in embedded or IoT applications

How to Use

1. Paste your XML document into the Input panel on the left
2. Click Format to prettify with syntax highlighting, or Validate to check well-formedness only
3. Review the element count, attribute count, and depth statistics shown in the output panel header
4. Click Copy Output to copy the formatted or minified result to your clipboard

Frequently Asked Questions

What is the difference between "Format" and "Validate"?

Both actions parse the XML and report errors. Format also re-serializes the document with consistent indentation and updates the output panel. Validate only checks well-formedness and shows the statistics without rewriting the output.

Does the validator check against an XML Schema (XSD)?

No. The tool checks XML well-formedness only (correct tag nesting, balanced tags, valid attribute syntax). Full schema validation against an XSD or DTD would require server-side processing and is not supported here.

Can this handle large XML files?

The tool works in the browser and can handle files up to several megabytes comfortably. Very large files (tens of MB) may cause the browser tab to slow down because the syntax highlighting and re-serialization are performed entirely in JavaScript.