Wonderstacked

Developer

XML Formatter

The XML Formatter pretty-prints messy or minified XML with consistent indentation and reports parse errors with their location. It uses the browser's native DOMParser and XMLSerializer, so your markup is validated and reformatted locally without ever being sent to a server.

Last updated · Free, no signup

Loading interactive XML Formatter…

What does an XML formatter check?

An XML formatter parses a document, reports structural syntax errors, and serializes valid markup with consistent indentation. It helps expose incorrect nesting, missing closing tags, invalid entities, and multiple root elements while making compressed configuration or feed data easier to review.

This implementation uses the browser's DOMParser and XMLSerializer without uploading the document. It checks whether XML is well formed; it does not validate the document against an XSD or DTD, so a syntactically correct file can still violate the vocabulary or data rules expected by another system.