Those Boring Tools
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YAML Formatter & Validator

Paste YAML to re-format it consistently and check it for syntax errors, entirely in your browser.

How to use this tool

  1. 1Paste your YAML into the input box.
  2. 2The formatted, re-indented YAML appears automatically.
  3. 3If there's a syntax error, the line and reason are shown.

Frequently asked questions

Does this support YAML anchors and multi-document files?+

Standard YAML 1.2 features including anchors, aliases, and common tags are supported. Multiple documents separated by `---` are parsed as the first document.

Can I convert YAML to JSON here?+

Yes — use the dedicated YAML to JSON converter for a side-by-side conversion; this formatter re-outputs as YAML.

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