JSON is lighter for APIs. XML still appears in feeds and enterprise documents. Choose based on the contract you must meet.
Different jobs
JSON maps cleanly to objects and arrays in JavaScript and Python. XML can describe mixed content, attributes, and namespaces. Neither is universally better.
APIs
Most public HTTP APIs now speak JSON. It is smaller and easier to parse in browsers. Validate and format it with the JSON validator and JSON formatter .
Documents and feeds
RSS, SOAP, and some publishing pipelines still use XML. If you receive YAML instead, the YAML JSON converter helps you inspect structure.
A practical rule
If you control both ends, pick JSON unless you need XML features. If a partner sends XML, convert at the edge rather than forcing JSON into a schema that needs attributes.
DNVERSE does not claim one format is obsolete. Use the contract in front of you.