YAML Formatter
Format YAML mappings, sequences, flow collections, comments, anchors, and scalar values with consistent indentation.
YAML input
Formatted YAML
Normalize YAML configuration
The formatter parses YAML as a document so comments and YAML-specific syntax can survive formatting. It also reports invalid indentation, duplicate keys, and malformed collections.
Frequently Asked Questions
Are YAML comments preserved?+
Yes. The document-based formatter retains comments while normalizing layout and indentation.
Does the formatter support anchors and aliases?+
Yes. Standard YAML anchors, aliases, block scalars, mappings, and sequences are supported.
Why are duplicate keys rejected?+
Duplicate mapping keys are ambiguous and can be interpreted differently by applications, so strict validation reports them as errors.
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