YAML: the config format DevOps fell in love with
YAML is a human-friendly superset of JSON that dominates CI/CD, Kubernetes and cloud configuration. Learn its rules and traps.
What YAML is
YAML (YAML Ain’t Markup Language) is a whitespace-sensitive, human-readable data serialisation format. It maps cleanly to the same object / array / scalar model as JSON, but drops braces and quotes in favour of indentation, making it much easier for humans to read and edit.
Where it rules
GitHub Actions workflows, Kubernetes manifests, Docker Compose files, Ansible playbooks, Netlify config, OpenAPI specs — all of them speak YAML.
Traps to avoid
Indentation must use spaces, never tabs. "yes", "no", "on", "off" resolve to booleans (this famously bit the Norway country code "NO"). Always quote values that might be misread. Our YAML Formatter surfaces syntax problems before they break your pipeline.
Convert to JSON in one click
YAML to JSON and JSON to YAML converters handle nested arrays, anchors and multi-line strings.
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