JSON vs XML: Differences, Examples and When to Use Each

If you work with APIs, config files or data exports, you will meet both formats. This guide shows the same data in JSON and XML, compares them feature by feature, and explains when each one is the better pick.

The same data in JSON and XML

Here is one small record written both ways.

JSON

{
  "book": {
    "id": 101,
    "title": "Data Basics",
    "inStock": true,
    "tags": ["data", "beginner"]
  }
}

XML

<?xml version="1.0" encoding="UTF-8"?>
<book id="101">
  <title>Data Basics</title>
  <inStock>true</inStock>
  <tags>
    <tag>data</tag>
    <tag>beginner</tag>
  </tags>
</book>

The JSON version needs fewer characters because it has no closing tags. It also knows that 101 is a number and true is a true or false value. In the XML version every value is text unless a schema says otherwise, and the id sits in an attribute instead of its own element.

JSON vs XML compared

See the official specs: RFC 8259 for JSON and the W3C XML 1.0 standard.

When to use JSON

• Web and mobile app APIs, where JSON is now the usual format
• Data that maps to objects and lists in code, especially JavaScript
• Config files for many web tools, such as package.json in Node.js
• Saving or sending data where small size and quick reading matter

When to use XML

• Documents that mix text and markup, such as books or legal texts
• RSS and Atom news feeds, and XML sitemaps for search engines
• Older enterprise systems and SOAP web services
• Files where strict checking against a schema is required
• Formats built on XML, such as SVG images and Microsoft Office files, which are zipped XML inside

Pros and cons

Can you convert JSON to XML?

Yes, and many tools do it. The match is not always one to one. XML attributes, comments and mixed text have no direct place in JSON, and JSON arrays need a chosen element name in XML. Check the output against what the receiving system expects.

Before you convert or send JSON, run it through the JSON formatter to catch missing commas, quotes and brackets.

Frequently asked questions

Is JSON replacing XML?

For new web APIs, JSON is the more common choice. XML is still widely used for documents, feeds, sitemaps, office files and many enterprise systems.

Is JSON faster than XML?

JSON files are usually smaller and quicker to read in JavaScript. Real speed depends on the parser, the language and the size of the data.

Can JSON have comments?

No. The JSON standard does not allow comments. Some tools accept them in config files, but standard JSON parsers will reject them.

Is HTML a type of XML?

No. HTML has its own rules and browsers accept code that XML would reject. XHTML is a version of HTML written as valid XML.

Which is easier to learn, JSON or XML?

Most people find JSON easier because it has fewer rules and looks like the lists and objects used in code.

Keep reading

• Try the JSON Formatter
• What Does JSON Stand For?
• Schema Markup Examples
• See all free tools