YAML Validator

About the YAML Validator

Checks YAML files for syntax errors, which is useful for configuration files such as Kubernetes manifests, Docker Compose files and CI pipelines.

How to use it

1. Paste your YAML into the editor.
2. Click Validate YAML.
3. If there is an error, the message shows what is wrong and where; fix it and validate again.

Good for

• Catching an indentation error before a deployment fails
• Checking a CI/CD pipeline file
• Validating Docker Compose or Kubernetes manifests

Tip: YAML does not allow tab characters for indentation, and a single misaligned space changes the structure. Validate before committing config changes.

Frequently asked questions

Why is my YAML invalid?

The most common causes are tab characters used for indentation, inconsistent spaces, and a missing space after a colon.

Can I validate Kubernetes or Docker Compose files?

Yes. They are plain YAML, so the validator checks their syntax. It does not check them against the Kubernetes or Compose schema.

Is my file uploaded?

No. Validation runs in your browser.

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