XML and JSON: What's the Difference
Compares XML and JSON through the trade-off between expressiveness and conciseness.
XML wraps data in tags and provides attributes, namespaces, and schema validation, giving it great expressiveness. In exchange, its repeated opening and closing tags make it verbose and heavy to parse.
JSON holds the same data far more compactly with minimal syntax. That is one reason most web APIs have moved to JSON. It is not, however, as mature as XML when it comes to comments or schema standardization.
Choose XML when you need legacy systems, document formats, or strict schemas, and JSON when the goal is lightweight, fast data exchange. When converting XML to JSON, you have to decide on a convention for how attributes and text are mapped.