Free XML Formatter & Validator Online — No Signup Required

XML (Extensible Markup Language) is a hierarchical data format used in SOAP web services, RSS and Atom feeds, SVG graphics, Microsoft Office documents, Android configuration files, Maven build files, and many enterprise data exchange formats. Raw XML is often minified or poorly indented, making it hard to read and debug. An XML formatter parses the document and re-outputs it with consistent indentation, making the tree structure immediately visible — a nested element that was hidden on line 1 becomes readable across dozens of lines.

This formatter validates XML as it parses, which means it catches structural errors: unclosed tags, missing attribute quotes, illegal characters, and encoding issues. The tool reports the line and character position of the first syntax error, so you can pinpoint the problem immediately rather than scanning thousands of characters of minified markup. It does not validate against an XML Schema (XSD) or DTD — it checks well-formedness only, which is sufficient for most debugging and formatting tasks.