YAML Formatter
Format standard YAML with readable indentation, duplicate-key checks, and bounded alias handling.
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How to use YAML Formatter
Reformat one YAML document using the standard core schema. Comments are retained where supported by the YAML parser, and unsafe custom tags are rejected.
- Paste one YAML document.
- Choose two or four spaces and run the formatter.
- Review the result before replacing a configuration file.
Good to know
- Standard YAML core schema only. Custom tags, duplicate keys, and multiple documents are rejected.
- Up to 100,000 input characters; aliases are bounded and shared or circular alias graphs are rejected.
- Formatting can normalize quoting and scalar styles; always review configuration changes.
Common questions
Can this execute YAML tags?
No. It does not install custom tag handlers, and unsupported tag warnings cause rejection.
Does it check my application configuration?
No. Valid YAML may still contain invalid settings for your application.
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