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.Use this in a chain

Indent:

YAML input

Formatted

name: ToolVaults
tools: 42
categories:
  - developer
  - text
  - color
features:
  pwa: true
  cmdk: true

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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