Developer Guide
YAML vs JSON
YAML vs JSON for configuration files: syntax, readability, comments, and when to use each. A practical comparison for DevOps and developers.
YAML and JSON are both used for configuration files and data interchange. Each has tradeoffs in readability, strictness, and tooling support.
Syntax differences
JSON uses braces, brackets, and requires quotes on all strings. YAML uses indentation, supports unquoted strings, and allows comments. YAML is a superset of JSON — valid JSON is valid YAML, but not vice versa.
Readability
YAML is more readable for humans due to its clean, indent-based syntax. JSON is more explicit and harder to misread. YAML's indentation sensitivity can cause subtle bugs when spaces and tabs mix.
Comments
YAML supports comments with #. JSON does not support comments (though JSONC does). This makes YAML better for annotated configuration files that need inline documentation.
When to use YAML
Kubernetes manifests, Docker Compose, GitHub Actions, Ansible playbooks. Human-edited configs where comments help. Files where readability matters more than strict parsing.
When to use JSON
API payloads, package.json, tsconfig.json, any machine-generated config. When you need strict parsing with predictable behavior. When your tooling expects JSON specifically.
Summary
Convert between YAML and JSON with the YAML-JSON Converter to use whichever format your tooling requires.