JSON (JavaScript Object Notation) and XML (eXtensible Markup Language) are two of the most popular data formats for storing and exchanging information. While both serve similar purposes, they have significant differences in syntax, readability, and use cases.
This comprehensive comparison examines JSON and XML across multiple dimensions to help you choose the right format for your specific needs. Learn more about JSON basics or explore Protocol Buffers vs JSON for even faster serialization.
Quick Overview
JSON
- •Lightweight and compact
- •Easy to read and write
- •Native to JavaScript
- •Faster parsing
- •Ideal for web APIs
XML
- •More verbose structure
- •Supports attributes and namespaces
- •Built-in validation (XSD)
- •Document-oriented
- •Ideal for complex documents
Syntax Comparison
The most obvious difference between JSON and XML is their syntax. Here's the same data represented in both formats:
JSON Example
{
"network": {
"device": {
"hostname": "router-01",
"ipAddress": "192.168.1.1",
"port": 443,
"protocols": ["SSH", "HTTPS", "SNMP"]
}
}
}XML Example
<?xml version="1.0" encoding="UTF-8"?>
<network>
<device>
<hostname>router-01</hostname>
<ipAddress>192.168.1.1</ipAddress>
<port>443</port>
<protocols>
<protocol>SSH</protocol>
<protocol>HTTPS</protocol>
<protocol>SNMP</protocol>
</protocols>
</device>
</network>Notice that XML requires opening and closing tags, making it more verbose. JSON uses a simpler key-value pair structure.
Feature Comparison
| Feature | JSON | XML |
|---|---|---|
| Readability | Easier to read | More verbose |
| File Size | Smaller | Larger |
| Parsing Speed | Faster | Slower |
| Data Types | String, Number, Boolean, Array, Object, Null | Everything is text |
| Arrays | Native support | No native arrays |
| Attributes | No attributes | Supports attributes |
| Namespaces | Not supported | Full support |
| Comments | Not supported | Supported |
| Schema Validation | JSON Schema | XSD (XML Schema) |
| Browser Support | Native in JavaScript | Requires parsing |
When to Use Each Format
Choose JSON When:
- •Building web APIs - RESTful services typically use JSON
- •Mobile applications - Smaller payload size saves bandwidth
- •JavaScript applications - Native support in JavaScript
- •Configuration files - Easy to read and write
- •Simple data structures - Straightforward hierarchical data
Choose XML When:
- •Document markup - XHTML, SVG, or document-centric data
- •Enterprise systems - SOAP web services, legacy integrations
- •Complex validation - Need strict schema validation (XSD)
- •Metadata requirements - Need attributes and namespaces
- •Standards compliance - Industry standards require XML
Performance Considerations
File Size
JSON is typically 30-50% smaller than equivalent XML due to less verbose syntax.
Parsing Speed
JSON parsing is generally 2-3x faster than XML parsing because of its simpler structure.
Memory Usage
JSON requires less memory to parse and store due to its compact representation.
Converting Between Formats
Need to convert between JSON and XML? Use our conversion tools:
JSON Tools
Continue Learning
External References
- •JSON.org - Official JSON specification
- •W3C XML - XML standards and documentation
- •W3Schools XML Tutorial - Learn XML basics