Comparison

JSON vs XML: Key Differences Explained

Published January 2026 • 6 min read

For decades, XML was the dominant format for exchanging structured data between systems. Then JSON came along and changed everything. Today, most new web APIs use JSON by default. But XML has not disappeared — it is still widely used in enterprise systems, document formats, and certain industries. So what exactly is the difference?

The Same Data, Two Formats

Here is the same data written in both formats, representing a book:

// JSON
{
  "title": "Clean Code",
  "author": "Robert C. Martin",
  "year": 2008,
  "available": true
}

<!-- XML -->
<book>
  <title>Clean Code</title>
  <author>Robert C. Martin</author>
  <year>2008</year>
  <available>true</available>
</book>

The JSON version is more compact and directly maps to native programming objects. The XML version is more verbose but has some capabilities JSON lacks.

Side-by-Side Comparison

Feature	JSON	XML
Readability	Clean, minimal syntax	Verbose, more markup
Data types	Supports strings, numbers, booleans, null, arrays, objects	Everything is text; types inferred by schema
Comments	Not supported	Supported with <!-- -->
Attributes	Not applicable	Elements can have attributes
Schema validation	JSON Schema (separate)	DTD / XSD (built-in ecosystem)
Browser support	Native JS parsing	Requires DOMParser
Typical use	REST APIs, config files, web apps	SOAP, enterprise, document formats

When to Use JSON

• Building or consuming a REST API
• Storing configuration or settings files
• Passing data between JavaScript frontend and backend
• Working with NoSQL databases like MongoDB

When XML Still Makes Sense

• Working with legacy enterprise systems (SOAP, EDI, WSDL)
• Document-centric formats like XHTML, SVG, or Office XML
• Situations requiring strict schema validation with XSD
• RSS/Atom feeds

Converting Between the Two

Sometimes you need to work with both. If you have XML data from a legacy system and need to pass it to a JSON-based API, you can use the XML to JSON converter on this site to transform it instantly in your browser.