YAML Validator - Format, Validate & Beautify YAML Online
Professional YAML validator and formatter with real-time validation, syntax highlighting, and error detection. Validate YAML syntax, format with proper indentation, minify for compact output, and beautify for readability—all in your browser with zero data transmission.
Key Features
This YAML validator provides everything you need for safe, efficient YAML processing—real-time validation, secure workflows, and clean output.
Real-time YAML Validation
Get instant feedback as you type. The validator checks YAML syntax, indentation, and structure, highlighting errors with precise line and column information.
Smart Formatting
Automatically format YAML with proper indentation while preserving anchors, aliases, comments, and multi-document separators. Keep your YAML readable and consistent.
One-Click Minify
Compress verbose YAML manifests into compact strings perfect for config maps, environment variables, or API payloads without losing data integrity.
Secure Browser-Based Processing
All validation and formatting happens entirely in your browser. Your YAML files never leave your device—perfect for sensitive Kubernetes configs and secrets.
Auto-Validation Toggle
Enable auto-validation to catch errors as you type, or disable it when editing raw manifests. Full control over when validation runs.
Undo-Friendly Editor
Complete undo/redo history lets you experiment with transformations safely. Never lose your work with full revision support.
How It Works
See how the YAML validator helps you create, validate, and format production-ready YAML files in seconds.
Paste your YAML directly into the editor or upload a YAML file. Supports single documents, multi-document streams, Helm values, and Kubernetes manifests.
Validation runs automatically as you type (if enabled). Use Format for clean indentation, Minify for compact output, or Validate to check syntax manually.
Errors are highlighted instantly with detailed messages showing exact line numbers, column positions, and error types. Green indicator confirms valid YAML.
Download the validated YAML, copy it to clipboard, or continue editing with full undo/redo support. All processing stays in your browser.
What YAML Validator Users Say
"The real-time validation catches YAML errors before they reach CI/CD. The error messages are precise and actionable—saves hours of debugging."
"Being able to validate and format YAML without installing tools has streamlined our workflow. The browser-based approach means no security concerns with sensitive configs."
"Client-side validation means I can validate kubeconfigs and secrets without any data leaving my machine. The structured error reporting is excellent for compliance audits."
YAML Validator FAQ
Does the validator change my YAML content?
Validation only checks syntax—it doesn't modify your YAML. Formatting adjusts indentation and whitespace but preserves all content, key order, anchors, aliases, and comments.
Can it validate multi-document YAML files?
Yes. The validator handles YAML streams with multiple documents separated by ---. Each document is validated independently, and document separators are preserved during formatting.
Is my YAML data sent to a server?
No. All validation and formatting happens entirely in your browser using JavaScript. No files, snippets, or data are transmitted to any server—your secrets stay secure.
Which YAML specification is supported?
The validator uses js-yaml with YAML 1.2 compatibility, making it safe for Kubernetes, Ansible, Helm, Docker Compose, and other modern YAML-based tools.
What if I make a mistake while editing?
Use the Undo button in the toolbar or standard keyboard shortcuts (Ctrl+Z / ⌘Z on Mac) to revert any changes. Full undo/redo history is maintained throughout your session.