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YAML Validator

Validate YAML syntax and convert to JSON. Detailed error messages with line numbers.

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What is YAML?

YAML (YAML Ain't Markup Language, spec 1.2.2) is a human-friendly data serialization standard. It's the de facto config language for modern DevOps — Kubernetes, Docker Compose, GitHub Actions, GitLab CI, Ansible, AWS CloudFormation, dbt, Hugo, Helm charts all use YAML. Its indentation-based structure makes configs readable, but also makes them fragile: a single misplaced space breaks the whole file.

Why a YAML validator matters

Most YAML errors don't fail loudly — they parse to different data than you intended. A missing dash, a tab character, or an unquoted "no" can silently change meaning. Validators catch syntactic errors immediately and show the corresponding JSON so you can verify the parsed data matches your intent.

Common contexts

  • Pre-commit: validate before committing K8s/Compose changes
  • CI debugging: "GitHub Actions failed parsing" — paste here to see exactly where
  • Schema migration: verify YAML maps cleanly to expected JSON
  • Helm value file checks: ensure templated values produce valid output

⚠️ Reference Only

Output is generated based on your input and is provided for reference. Results may vary depending on your specific use case, edge cases, or environment-specific behavior. We do not guarantee accuracy of conversions, validations, or computed values.

Always verify critical outputs against official documentation or production environments. We are not responsible for any decisions or losses based on these tool results.