DevToolKit

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) is a human-readable data serialization format widely used for configuration files, CI/CD pipelines (GitHub Actions, GitLab CI), Kubernetes manifests, and Docker Compose files. Its indentation-based structure makes it easy to read but also easy to get wrong — a single misplaced space can break an entire config.

Common YAML Mistakes

Tabs vs. spaces (YAML only allows spaces), missing colons after keys, incorrect indentation levels, and unquoted special characters like colons or hashes inside values are the most frequent sources of YAML errors.