Paste your YAML below to validate it instantly. See the parsed structure as JSON to verify your YAML is correct.
YAML stands for YAML Ain't Markup Language. It is a human-readable data serialisation format used in configuration files. Docker Compose files, Kubernetes manifests, GitHub Actions workflows, and many other tools use YAML for their configuration. YAML uses indentation to represent structure which makes it readable but also easy to break with incorrect indentation.
Common YAML mistakes include using tabs instead of spaces for indentation, inconsistent indentation levels, missing colons after keys, and incorrect string quoting. This tool catches all of these errors and shows you exactly where the problem is.
YAML is a superset of JSON - all valid JSON is valid YAML. YAML is more human-friendly for writing by hand because it does not require quotes around strings, curly braces around objects, or commas between items. JSON is better for machine generation and API responses.
No. YAML does not allow tabs for indentation. You must use spaces. This is the most common source of YAML errors. Most text editors can be configured to insert spaces when you press the Tab key.
Yes. Everything runs in your browser. Your YAML is never sent to any server.