JSON vs YAML
Both serialize structured data, but they optimize for different priorities.
| Feature | JSON | YAML |
|---|---|---|
| Readability | Good (curly braces, quotes) | Excellent (indentation-based) |
| Comments | Not supported | Supported (#) |
| Data types | string, number, boolean, null, array, object | All JSON types + dates, multi-line strings, anchors |
| Parsing speed | Fast (simple grammar) | Slower (complex grammar) |
| File size | Larger (quotes, brackets) | Smaller (no quotes needed) |
| Whitespace | Insignificant | Significant (indentation matters) |
| Native web support | Yes (JSON.parse built-in) | No (requires library) |
| Multi-document | No | Yes (--- separator) |
When to use JSON
- APIs and web services (industry standard)
- JavaScript/TypeScript projects (native support)
- Data interchange between services
- When parsing speed matters
- package.json, tsconfig.json, and other tool configs
When to use YAML
- Configuration files humans edit often (Docker Compose, Kubernetes, GitHub Actions)
- When you need comments in config
- CI/CD pipelines
- Ansible playbooks, Helm charts
- When readability trumps parsing speed
Quick syntax comparison
JSON
{
"name": "DevKit",
"version": "1.0.0",
"features": ["tools", "cheatsheets"],
"config": {
"port": 3000,
"debug": false
}
}YAML
# Project config name: DevKit version: "1.0.0" features: - tools - cheatsheets config: port: 3000 debug: false
Bottom line
Use JSON for machine-to-machine data exchange. Use YAML for human-edited configuration. Convert between them with our YAML ↔ JSON Converter.