XML explained: still relevant, still everywhere
XML is older than JSON but still runs enterprise systems, config files and document formats. Here is what you need to know.
What XML is
XML (eXtensible Markup Language) is a self-describing, tag-based text format designed for storing and transporting data. Every value lives inside a named element, and every element can have attributes, child elements and text content. Unlike HTML, XML has no built-in tags — you invent the vocabulary that fits your data.
Where it lives today
XML powers SOAP web services, legacy enterprise integrations, Office documents (docx, xlsx are ZIPped XML), Android manifests, RSS feeds, SVG images and countless configuration files.
Well-formed vs valid
An XML document is well-formed when every start tag has a matching end tag and elements are properly nested. It is valid when it also conforms to a schema (XSD or DTD). Our XML Formatter checks well-formedness and highlights mismatched tags so you can catch broken markup instantly.
Convert freely
Need XML as JSON or YAML? Use the XML to JSON and XML to YAML converters — attributes are preserved with an @_ prefix so no information is lost.
Try it in Code Formatter Pro
Every tool mentioned in this article runs entirely inside your browser — no signup, no uploads.
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