Developer Tools

YAML Validator

Paste any YAML and get instant validation with exact error location. Supports YAML 1.2 including anchors, aliases, multi-document streams, and all scalar types, ideal for Kubernetes manifests, Docker Compose, and config files.

Runs in your browser No data sent to servers Copy or download result
yaml YAML to validate
Runs in your browser; code never leaves your device
Input Text Output Report Browser-only No upload by default

Features

  • YAML 1.2 syntax validation
  • Exact error line and column
  • Anchors and aliases supported
  • Multi-document stream validation
  • Shows parsed structure summary on success

How to use it

  1. Paste your YAML in the input panel.
  2. Validation runs instantly.
  3. Fix any errors shown with line/column info.
  4. Valid YAML shows a structure summary.

Use cases

  • Validating Kubernetes manifests before kubectl apply
  • Checking GitHub Actions workflow files
  • Debugging Docker Compose YAML
  • Verifying CI configuration files

Limitations

  • The parser focuses on common mappings, lists, booleans, numbers, and strings.
  • Very large input can be slower on older devices.
  • This utility is designed for common snippets and local inspection, not as a full security or language-specific validator.
See also

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Questions & answers

Frequently asked

What YAML version is supported?

YAML 1.2 with full support for anchors, aliases, block and flow styles, and multi-document streams.

Does YAML Validator upload my input?

Your file or text is processed in your browser and is not uploaded.

What does YAML Validator output?

It outputs a YAML validation report. The parser focuses on common mappings, lists, booleans, numbers, and strings.

Should I review YAML Validator output before using it?

Yes. Developer formats and snippets can be context-sensitive, so review generated output before using it in production.