📄 YAML Formatter, Validator & YAML ↔ JSON

Format and validate YAML, or convert between YAML and JSON. Parse errors surface with line numbers, and the YAML 1.1 schema is used (so yes/no/on/off are booleans unless quoted). All work happens in your browser.

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❓ FAQ

YAML or JSON for config?

YAML wins for human-edited config (comments, less noise). JSON wins for machine-to-machine. Many tools accept both.

"Norway Problem"?

YAML 1.1 parses NO as false — quote it as "NO" to keep it a string. YAML 1.2's core schema fixes this; many tools still default to 1.1.

Is my data uploaded?

No. Parsing happens in your browser via js-yaml.

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