JSON vs XML: Which Is Better and Why Everyone Switched to JSON

If you've worked with APIs, configured settings, or exchanged data between systems — you've definitely encountered JSON and XML. These two formats are like brothers who went their separate ways. One is lightweight and fast, the other is thorough and strict.

I remember my first steps in development: we used XML for everything. Configs, APIs, server responses — everywhere there was this bulky tag-based language. Then JSON appeared, and everything changed.

Let's figure out what the difference is, which is better, and why the industry massively switched to JSON.

What is JSON?

JSON (JavaScript Object Notation) is a lightweight data exchange format based on JavaScript syntax. It was created in the early 2000s and quickly gained popularity due to its simplicity.

Here's what JSON looks like:

{
  "user": {
    "id": 123,
    "name": "John Doe",
    "email": "john@example.com",
    "isActive": true,
    "hobbies": ["reading", "programming"]
  }
}

Simple, readable, clear. It's like an object in JavaScript — no wonder it's called that.

What is XML?

XML (eXtensible Markup Language) is an extensible markup language. It appeared in the late 90s and was meant to replace HTML for data transmission.

Here's what XML looks like:

<?xml version="1.0" encoding="UTF-8"?>
<user>
  <id>123</id>
  <name>John Doe</name>
  <email>john@example.com</email>
  <isActive>true</isActive>
  <hobbies>
    <hobby>reading</hobby>
    <hobby>programming</hobby>
  </hobbies>
</user>

As you can see, XML uses tags like HTML. Data is wrapped in opening and closing tags, making the format self-documenting.

JSON vs XML — Comparison

Let's look at the key differences in a table:

Why JSON Is Better (and Why Everyone Switched)

When I first tried JSON, I knew there was no going back. Here's why:

• Compactness

  JSON takes 40-60% less space than XML. Less data = faster transfer = less traffic.

• Parsing speed

  JSON parses many times faster. In JavaScript, it's a built-in JSON.parse() function.

• JavaScript compatibility

  JSON is almost a ready-made JavaScript object. For frontend developers, it's a dream.

• Readability

  JSON is easier to read. Fewer characters, less visual clutter.

Where XML Is Still Used

Despite JSON winning, XML hasn't died. It's still alive and used in some areas:

• SOAP web services

  An old but resilient standard for enterprise integrations

• Configuration files

  For example, in Java (pom.xml, web.xml), Android (AndroidManifest.xml)

• RSS and Atom feeds

  Many news sites still serve RSS in XML

When to Choose What — Practical Advice

Working with JSON and XML in Different Languages

JavaScript (JSON parsing)

const data = JSON.parse(jsonString);
console.log(data.user.name);

JavaScript (XML parsing)

const parser = new DOMParser();
const xmlDoc = parser.parseFromString(xmlString, "text/xml");
const name = xmlDoc.getElementsByTagName("name")[0].textContent;

Python (JSON parsing)

import json
data = json.loads(json_string)
print(data['user']['name'])

Python (XML parsing)

import xml.etree.ElementTree as ET
root = ET.fromstring(xml_string)
name = root.find('name').text

As you can see, working with JSON is simpler and requires less code.

Frequently Asked Questions

In Conclusion

I use JSON everywhere I can. APIs, configs, data storage — everything in JSON. I leave XML for those rare cases when I'm working with SOAP or legacy systems.

My advice: use JSON for everything new. It will save you time, nerves, and traffic. Leave XML for compatibility when it's truly necessary.