YAML Validator & Linter
Lint and audit YAML files for prohibited tab characters, colon spacing rules, quote mismatches, and document structure validity.
Clean
16
13
1
No prohibited tab indentation violations, missing colon spaces, or quote mismatches detected.
Client-Side YAML Syntax & Tab Indentation Audit
YAML relies strictly on space-based indentation. Using tab characters or omitting a space after a key colon (`key:value` instead of `key: value`) causes silent syntax failures in Docker Compose, Kubernetes, and Ansible deployments.
The YAML Validator provides an instant, client-side linter to audit YAML configuration files for prohibited tabs, key-colon spacing errors, unclosed quotes, and document boundary issues.
Core Tool Capabilities
- Prohibited Tab Detection: Flags tab characters used for indentation (violating the YAML spec).
- Colon Spacing Audit: Detects missing space after key colons in key-value mapping lines.
- Quote Matching: Identifies unmatched single or double quotes across string scalars.
- Document Metrics: Summarizes total lines, document count, and key entry totals.
Local Browser Privacy
Your files are processed locally on your device. Files are not uploaded, transmitted, or stored on remote servers.
Once the page has loaded, you can disconnect your network connection and continue using this tool offline.
Target Use Cases
- • Docker Compose Validation
- • Kubernetes Manifest Linting
- • Ansible & CI Configuration
Technical Specifications & Platform Limits
Strict space indentation and mapping key checking
Evaluated in local JavaScript memory
No external network calls or cloud logging
Step-by-Step Workflow
Paste YAML Content
Paste your YAML configuration file into the code editor.
Automatic Linting
The validator instantly scans the document for syntax and tab errors.
Review Error Reports
Check the error list for exact line numbers and column positions.
Fix Indentation & Retry
Correct tab or spacing errors directly in the editor until valid.
Practical Real-World Use Cases
Docker Compose Validation
Developers audit docker-compose.yml files for tab or mapping errors before running docker-compose up.
Kubernetes Manifest Linting
Developers validate k8s deployment and service YAML manifests prior to kubectl apply.
Ansible & CI Configuration
Developers lint Ansible playbooks and GitHub Actions workflow files.
Frequently Asked Questions
- Why does YAML forbid tab characters?
- The YAML specification prohibits tab characters for indentation because different text editors render tabs with varying width, leading to ambiguous document structure.
- Is my YAML file sent to an external server?
- No. All linting and validation operations take place Full locally inside your browser.
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