YAML validator, formatter and JSON converter
Paste YAML to check it and tidy the indentation, or convert between YAML and JSON. Errors show the line and column. It keeps your comments and runs in your browser.
Runs in your browser, nothing is uploadedTry an example:,,
YAML with several documents (separated by ---) is supported. Converting to JSON turns several documents into a list. Do not paste secrets: nothing is sent anywhere, but it is a good habit.
How to use the Kubernetes YAML validator
- Paste a manifest or workflow. Several documents separated by --- are fine.
- Press Format YAML. If something is wrong, the error shows the exact line and column; if not, you get tidy, consistently indented YAML.
- Need JSON for an API or a policy? Use YAML to JSON, or JSON to YAML for the other direction.
Example: the tab that breaks a deploy
A Deployment fails in CI with a vague parse error. Pasted here, the validator points to line 18: a tab before "image:". YAML only allows spaces for indentation.
Another common one is version: 1.10 being read as the number 1.1. Quote values that look like numbers when they must stay text.
Common questions
Does it check Kubernetes fields too?
It checks that the YAML is valid and well formed. To check fields against the Kubernetes schema, run kubectl apply --dry-run=server or kubeconform in your pipeline.
Does it keep my comments?
Yes. Formatting keeps comments. Converting to JSON drops them, because JSON has no comments.
Does it work for GitHub Actions workflows?
Yes. Paste the workflow file to catch indentation and quoting mistakes before you push.
Read next: 3 YAML mistakes that break Kubernetes and GitHub Actions deploys
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