JSON vs YAML vs XML
A comprehensive comparison of the three most popular data serialization formats.
| Feature | JSON | YAML | XML |
|---|---|---|---|
| Human Readable | ⭐⭐⭐ | ⭐⭐⭐⭐⭐ | ⭐⭐ |
| File Size | Small | Smallest | Large |
| Parse Speed | Fast | Medium | Medium |
| Comments | ✗ No | ✓ Yes (#) | ✓ Yes |
| Schema Support | JSON Schema | Limited | XSD, DTD |
| Native Browser | ✓ Yes | ✗ No | ✓ Yes |
{ } JSON
JavaScript Object Notation - the most popular data interchange format for web APIs.
EXAMPLE
{
"name": "John",
"age": 30,
"active": true
}✓ PROS
- • Native JavaScript support
- • Compact and fast parsing
- • Widely supported in APIs
- • Simple syntax
✗ CONS
- • No comments allowed
- • No multiline strings
- • Strict syntax
--- YAML
YAML Ain't Markup Language - human-readable format popular for configuration files.
EXAMPLE
name: John age: 30 active: true # This is a comment
✓ PROS
- • Most human readable
- • Supports comments
- • No brackets or quotes
- • Multi-document support
✗ CONS
- • Indentation sensitive
- • Slower parsing
- • No browser support
</> XML
eXtensible Markup Language - powerful format for document-centric data.
EXAMPLE
<person> <name>John</name> <age>30</age> <active>true</active> </person>
✓ PROS
- • Powerful schema validation
- • Supports attributes
- • Namespaces support
- • XPath/XSLT transformation
✗ CONS
- • Very verbose
- • Large file sizes
- • Complex to parse
📌 When to Use Each Format
Use JSON for:
- ✓ REST APIs & web services
- ✓ Browser-based applications
- ✓ Mobile app backends
- ✓ Package managers (npm, composer)
- ✓ NoSQL databases (MongoDB)
Use YAML for:
- ✓ Configuration files
- ✓ Docker Compose
- ✓ Kubernetes manifests
- ✓ CI/CD pipelines (GitHub, GitLab)
- ✓ Ansible playbooks
Use XML for:
- ✓ SOAP web services
- ✓ Office documents (DOCX, XLSX)
- ✓ SVG graphics
- ✓ RSS/Atom feeds
- ✓ Enterprise systems (XBRL)
📊 Size Comparison
The same data represented in each format:
JSON~50 bytes
{"name":"John","age":30}YAML~22 bytes
name: John age: 30
XML~80 bytes
<r><name>John</name> <age>30</age></r>
Convert between formats instantly