Format, beautify, minify, and validate XML instantly — 100% browser-based. No data is ever sent to any server.
XML (eXtensible Markup Language) remains a cornerstone of enterprise software, web services, configuration files, and data interchange formats such as SOAP, WSDL, Android layouts, Maven POM files, RSS feeds, and SVG images. Working with raw or machine-generated XML is often painful because it arrives as a single unreadable line. This formatter uses the browser's built-in DOMParser API to parse and serialize XML — the same parser your browser uses to render web pages. Because everything happens locally in JavaScript, your data never leaves your device. The validator catches common XML problems such as unclosed tags, mismatched tag names, illegal characters, and missing root elements, and reports the error message directly from the parser so you get precise, actionable feedback.
Well-formed XML follows the basic syntax rules of XML: every tag must be closed, tags must be properly nested, and there must be exactly one root element. Valid XML additionally conforms to a schema (DTD or XSD) that defines which elements and attributes are allowed and in what order. This tool checks for well-formedness, which is the first requirement before any schema validation can occur.
The browser's XML parser is strict. Common causes include: an ampersand (&) that isn't escaped as &, angle brackets (< or >) used as literal characters outside of CDATA sections, mismatched or unclosed tags, or multiple root elements. The error message in the status bar will point to the specific issue so you can fix it quickly.
Yes — since the formatting runs entirely in your browser with no upload size limit, you can process XML files of any size that your browser tab can hold in memory. For extremely large files (tens of megabytes), performance depends on your device. For files in the gigabyte range, a dedicated command-line tool like xmllint --format would be more appropriate.
Yes. The formatter preserves XML namespaces (xmlns declarations and prefixed elements) and CDATA sections (<![CDATA[...]]>) exactly as written. Processing instructions (<?xml ...?>) and XML comments (<!-- ... -->) are also preserved in the output.