Nadhebe

YAML Syntax Validator & Linter

YAML CODE INPUT

VALIDATION & LINT REPORT
Validation Status
Valid YAML Syntax ✓

0 Indentation or Syntax Errors Detected

Parsed YAML Structure Summary
 

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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