YAML Validator & Formatter
Paste YAML to validate syntax and see the parsed JSON. Everything runs locally in your browser.
What is YAML?
YAML (YAML Ain't Markup Language) is a human-friendly data serialization format commonly used for configuration files. It's easier to read and write than JSON or XML, making it popular for tools like Docker Compose, Kubernetes, GitHub Actions, and CI/CD pipelines.
YAML uses indentation to represent structure (similar to Python), supports comments, and has a clean syntax without curly braces or brackets. However, indentation errors can break your YAML, making validation essential.
This validator parses your YAML and shows the equivalent JSON structure. If there are syntax errors, it displays the exact line and reason. Unlike other online validators, qtoolkit.dev processes everything client-side in your browser, so your configuration files never leave your machine.
Common YAML Errors
Mixing tabs and spaces for indentation, incorrect indentation levels, unescaped special characters in strings, missing colons after keys, and inconsistent list syntax. This validator catches all of these.