JSON vs YAML for configuration

• A machine writes it, not a human — API responses, generated config, lockfiles.
• You need unambiguous parsing with no whitespace sensitivity.
• The consuming tool already expects JSON and you’d otherwise add a conversion step.
• You want strict validation to catch typos early — JSON has no silent type coercion.

• Humans hand-edit it regularly — comments and a less noisy syntax matter.
• The ecosystem already standardized on it — Kubernetes manifests, most CI pipeline configs.
• You need multi-line strings (log formats, scripts embedded in config) without escaping.

YAML’s readability comes from significant whitespace and a permissive grammar — the same features that make it pleasant to write also make it easy to break silently. A single misplaced space changes structure without an obvious syntax error. The common YAML indentation errors guide covers the specific failure modes. JSON’s stricter grammar trades that readability for parse failures that are loud and immediate instead of silent.

Structurally, JSON is a subset of YAML — any valid JSON document is also valid YAML. Going the other way (YAML → JSON) loses comments and YAML-specific features like anchors and aliases, since JSON has no equivalent. Format and validate either format directly with the JSON Formatter and Validator or the YAML Formatter and Validator.