XML vs JSON for data feeds: when XML still wins
JSON won the API era, but XML still runs sitemaps, RSS, SOAP, and countless B2B feeds. A pragmatic look at where each format fits.
It is tempting to treat XML as legacy. But the moment you look at sitemaps, RSS and Atom feeds, SOAP services, government open data, financial messaging, and a huge share of B2B integrations, XML is very much the present tense.
The useful question is not which format is better, but where each one fits.
Where XML still wins
- Namespaces let independent vocabularies coexist in one document without collisions.
- Schemas (XSD) and validation are mature, expressive, and widely tooled.
- Mixed content — markup interleaved with text — is native, which matters for documents.
- Attributes plus elements give a second axis of structure that maps cleanly to many domains.
- Enormous existing surface area: sitemaps, feeds, SOAP, and industry standards are not going anywhere.
Where JSON is the better default
For internal APIs and anything that maps naturally to objects and arrays, JSON is lighter and easier to work with. If you control both ends and there is no schema or namespace requirement, reach for JSON.
The pragmatic middle
Most teams live in both worlds: JSON for their own services, XML for the feeds and partners they do not control. The work is not choosing a side — it is making the XML you depend on visible, searchable, and monitored so it stops being a black box.
That is exactly the gap XMLDir is built to close.