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Validate Kubernetes YAML manifests for required fields, container specs, resource limits, and common misconfigurations
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Enter K8s YAML manifest and click Validate
A Kubernetes YAML validator checks your K8s manifest files for common configuration errors, missing required fields, and best-practice violations before you apply them to a cluster. Applying invalid manifests to a live cluster can cause deployments to fail, services to malfunction, or security vulnerabilities to emerge. This tool parses your YAML manifests and performs rule-based validation across multiple checks: required metadata fields (apiVersion, kind, name), container specifications (image, ports), resource limits and requests, label and selector matching, port conflict detection, and environment variable validation.
This validator is an essential part of any DevOps workflow — it acts as a linting step between writing a manifest and applying it with kubectl apply. It helps catch issues early, reduces deployment failures, and enforces consistency across your team's Kubernetes configurations. Developers, platform engineers, and SREs use this tool daily to validate manifests before merging pull requests or deploying to staging environments.
What types of issues does this validator detect?
It checks for missing required fields (name, apiVersion, kind), empty or misconfigured container specs (missing image, port conflicts), label selector mismatches between services and deployments, missing resource requests/limits, invalid port values, and duplicate resource names within a manifest.
Does this connect to a live Kubernetes cluster?
No. All validation is performed locally in your browser using static analysis of the YAML content. No connection to any Kubernetes API server is required or made.
Can it validate CRDs (Custom Resource Definitions)?
The validator checks for basic structural correctness in any resource — ensuring apiVersion and kind are present, metadata is properly formatted, and required fields are populated. For CRD-specific validation against your custom schema, you would need a cluster-side admission webhook.
Is my YAML data sent to a server?
No. All processing occurs locally in your browser. Your manifests never leave your device, making this safe for validating sensitive configuration files.
How is this different from kubectl apply --dry-run?
kubectl apply --dry-run=client performs server-side schema validation, which requires kubectl and cluster access. This tool provides client-side best-practice checks that work offline and don't require any Kubernetes tooling installed — simply paste and validate from any browser.
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