How do I validate YAML syntax?

Paste your YAML into the YAML Formatter. It validates syntax and highlights errors with line numbers. Common issues include mixed tabs/spaces, wrong indentation levels, and unquoted special strings.

Can I use tabs in YAML?

No. YAML requires spaces for indentation — tabs are explicitly forbidden by the spec. This is the most common YAML error. Configure your editor to insert spaces when you press Tab in YAML files.

What is the difference between YAML and JSON?

YAML supports comments, multi-line strings, and anchor/alias references. JSON is stricter with no comments. YAML uses indentation for structure; JSON uses braces and brackets. Both represent the same data structures.

How to Format and Validate YAML

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