Instantly validate and format YAML. Catches indentation errors, invalid syntax, and duplicate keys with exact line numbers. Free, no login.
Supports: Kubernetes Deployment/Service · Docker Compose · GitHub Actions · GitLab CI
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YAML schema validation with auto-detection that identifies your YAML format from content patterns.
| Schema | Version | Auto-detection |
|---|---|---|
| Kubernetes Deployment | v1.29 | apiVersion + kind: Deployment |
| Kubernetes Service | v1.29 | apiVersion + kind: Service |
| Docker Compose | v2.29 | services field |
| GitHub Actions | workflow | on + jobs fields |
| GitLab CI | latest | stages array |
A YAML validator checks your YAML document for syntax errors such as incorrect indentation, invalid characters, duplicate keys, and structural issues — giving you exact line numbers and error messages.
Common YAML errors include: inconsistent indentation (mixing tabs and spaces), missing colons after keys, unquoted special characters like colons or hash signs in values, duplicate keys, and incorrect list formatting.
Yes — this tool validates any YAML including Kubernetes manifests, Docker Compose files, GitHub Actions workflows, Helm values files, Ansible playbooks, and more.
No — YAML does not allow tabs for indentation. You must use spaces only. This is one of the most common causes of YAML validation errors.
YAML is the backbone of Kubernetes and Terraform. Start our free tutorials to put your validated YAML to work.