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YAML vs JSON: when to use each format

Compare readability, tooling, and trade-offs for configuration and APIs.

2026-05-28 · 5 min read

YAML emphasizes human readability with indentation and comments. JSON emphasizes strict syntax and universal parser support. Many platforms accept both; choosing wisely reduces operational pain.

Prefer YAML when

  • Humans edit configs by hand (Kubernetes, CI pipelines)
  • Comments document non-obvious settings
  • Nesting is deep but still readable with indentation

Prefer JSON when

Converting between formats is easy for simple trees but lossy for comments and YAML-specific types.

  • Machines generate and consume data exclusively
  • You need the strictest cross-language compatibility
  • Comments must not appear in the serialized form

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