Finding a bad indent
A pipeline that fails to parse has a list item indented one space too far; the validator points at the line.
Use YAML Validator
Converts yaml to result in this tab, with nothing sent anywhere.
Runs entirely on your deviceThe conversion happens in this browser tab. Nothing you type is uploaded, logged or stored, which is worth knowing for anything you would not paste into a search box.
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Browse all developer and data toolsAbout YAML Validator
YAML runs the world's configuration - CI pipelines, Kubernetes manifests, application settings - and its greatest strength, that whitespace carries meaning, is also its most common trap. One stray space, a tab where spaces were expected, or a misaligned list item changes the structure or breaks parsing entirely, often with an error that appears far from the real mistake. This validator loads your YAML in the browser and tells you whether it parses, and on failure reports the line and column the parser stumbled on. Running locally matters here more than almost anywhere: pipeline and deployment YAML is riddled with secrets, hostnames and internal detail that should never be pasted into an unknown site.
Using YAML Validator
- Paste your YAML. It is parsed on your device with the same library real tools use; nothing leaves the tab.
- A valid document is confirmed with a note on its top-level shape - a mapping with so many keys, or a list of items.
- An invalid one is reported with the line and column where parsing failed, which is usually at or just after the indentation mistake.
Where yaml validator helps
Checking a manifest
Confirm a Kubernetes or Compose file is well-formed YAML before applying it, catching structural errors early.
Before you use the result
- Indentation must use spaces, not tabs; a tab in a YAML file is one of the most common and most confusing causes of failure.
- It validates syntax, not whether the keys match a particular tool's schema. A valid file can still be rejected by Kubernetes or a CI system for using the wrong fields.
- Validation is inherently one-way: there is no inverse operation to reverse, unlike the format converters elsewhere on the site.
Questions about YAML Validator
Why does YAML break so easily?
Because indentation defines structure. A misplaced space, or a tab instead of spaces, silently changes the shape or stops it parsing. The validator shows where.
Can it validate against a schema?
No - it checks that the YAML parses. Whether it has the right fields for Kubernetes, GitHub Actions or another tool is a separate schema check.
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