YAML Validator
Validate YAML indentation, quotes, and structure in your browser. Free YAML checker for config files, no upload.
Processed locally in your browser.
How to use this yaml validator
Paste YAML. The validator checks 2-space indentation, unclosed quotes, skipped indent levels, and incomplete list items.
It covers common config YAML (CI, Docker Compose, Kubernetes-style maps). It is not a full YAML 1.2 implementation with every tag and merge key.
Example
A mapping like name: ada with a child indented two spaces is valid. Mixing tabs or jumping four extra spaces is flagged.
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Frequently asked questions
Why is my YAML invalid?
Tabs, odd indent widths, and unclosed quotes are the usual issues. YAML is indentation-sensitive.
Is this a YAML linter?
It is a structural checker, not a schema linter for Kubernetes or GitHub Actions.
Is YAML uploaded?
Processed locally in your browser. We do not upload the text to compute a result.
Last reviewed 2026-08-19. Results stay on your device unless you copy them elsewhere.