YAML Validator
Validate YAML syntax instantly — no upload, fully private. 100% free.
Built for Obsidian, Hugo, Jekyll, and CI pipelines.
How to use
- Paste your YAML into the box on the left.
- The validator reports whether it parsed successfully.
- Fix any errors using the message shown on the right.
If your YAML is valid you will see a confirmation; if not, the exact error is reported.
Example
name: example
list:
- one
- two
nested:
key: value✓ Valid YAML
6 line(s) parsed successfully.When this works best
It reports valid/invalid but does not reformat your text. It follows the YAML 1.2 spec via js-yaml, so YAML 1.1-only features (e.g. sexagesimal numbers) may be rejected.
How it differs from related tools
The YAML Frontmatter Validator & Fixer only checks the --- block of Markdown notes; this tool validates any YAML document, anywhere.
Frequently asked questions
Does the validator upload my YAML?
No. Validation happens on your device; nothing is sent to a server.
What YAML version is supported?
The validator follows the YAML 1.2 spec via js-yaml.
Can it fix my YAML?
No — it only reports valid or invalid. For auto-fixing, try the YAML Formatter or the Frontmatter Fixer.
Does it follow YAML 1.2 exactly?
Yes, via js-yaml. Some YAML 1.1-only constructs (such as sexagesimal numbers) are rejected.