YAML Syntax Validator & Linter
YAML CODE INPUT
0 Indentation or Syntax Errors Detected
YAML Validation & Indentation Standards Guide
YAML (YAML Ain't Markup Language) is the standard configuration format for DevOps pipelines, GitHub Actions workflows, Kubernetes deployments, and OpenAPI specifications.
Common YAML Lint Errors
- Tab Characters: Using tabs instead of 2 spaces causes parse failures.
- Colon Spacing: Keys must be followed by a space after the colon (
key: value). - Unquoted Special Characters: Strings containing colons,
@, or%require double quotes.
Related Developer Tools
Convert YAML to JSON with the YAML to JSON Converter, generate OpenAPI schemas with the OpenAPI 3 YAML Generator, or validate JSON schemas with the JSON Schema Validator.
Frequently Asked Questions
Common questions about this tool.
How does the YAML Syntax Validator work? ▼
The validator parses your YAML text line-by-line client-side, checking indentation rules, tab character usage, colon key-value formatting, and array dash syntax.
Why does YAML throw indentation errors? ▼
YAML requires consistent space indentation (typically 2 spaces per level). Using TAB characters instead of spaces violates the YAML specification and causes parser errors.
Can I validate Kubernetes or Docker Compose YAML files? ▼
Yes! Paste your `docker-compose.yml` or K8s `deployment.yaml` manifest into the editor to verify syntax correctness before running `kubectl apply`.
Is my YAML code uploaded to external servers? ▼
100% private. All validation and linting execute locally in your web browser.
How can I convert valid YAML to JSON? ▼
Use our dedicated <a href="/tools/yaml-to-json/">YAML to JSON Converter</a> tool to transform valid YAML manifests into JSON objects.
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