YAML Formatter & Validator
Format and validate YAML in your browser. Multi-document (---) supported. Errors point to line and column. YAML 1.2 spec.
Runs 100% in your browser — nothing is uploaded.
Formatted
Frequently asked
Which YAML spec?
YAML 1.2, via the mature `yaml` npm package running entirely in your browser.
Are comments preserved?
No. Formatting round-trips through JavaScript objects, which strip comments. If you need comment preservation, edit YAML directly rather than round-tripping.
Multi-document files?
Yes — YAML lets you separate documents with `---`. The formatter parses each and re-emits them separated the same way.
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