YAML Validator

Validate YAML syntax and structure with detailed error reporting

YAML Input

Enter or paste YAML data to validate syntax and structure

Validation Results

What is YAML Validation?

YAML validation checks if your YAML document follows correct syntax rules and structure. This tool validates YAML entirely in your browser - your data never leaves your device. It's essential for catching errors in configuration files before deployment, especially for Docker, Kubernetes, CI/CD pipelines, and other DevOps tools.

How to Use

Paste your YAML data into the input field
Click "Validate YAML" to check for syntax errors
Review any errors with line and column numbers
Use "Analyze Structure" to see document type and keys
Fix errors and re-validate until your YAML is correct

Example

Valid YAML:

name: John Doe
age: 30
address:
  city: New York
  zip: 10001
skills:
  - JavaScript
  - Python
  - Docker

Invalid YAML (incorrect indentation):

name: John Doe
  age: 30  # Error: bad indentation
address:
  city: New York

Features

Validate YAML syntax with detailed error messages
Display error line and column numbers for easy debugging
Analyze document structure (object, array, or scalar)
Optional JSON schema validation support
Detect common errors: indentation, quotes, colons, brackets
100% client-side processing for privacy
Supports nested objects, arrays, and special characters
Works with Kubernetes, Docker Compose, and CI/CD configs

Common YAML Errors

Incorrect indentation: YAML uses spaces (not tabs) for indentation. Each level must be consistently indented.
Missing colons: Key-value pairs require a colon and space (key: value).
Unclosed quotes: Strings with quotes must be properly closed.
Invalid characters: Some special characters need to be quoted.
Mixed indentation: Don't mix tabs and spaces - use spaces only.

When to Use YAML Validator

Before deploying Kubernetes manifests or Helm charts
When editing Docker Compose files
Before committing CI/CD pipeline configurations
When troubleshooting configuration file errors
To verify YAML structure before conversion to JSON
When learning YAML syntax and best practices

Frequently Asked Questions

What is YAML validation?

YAML validation checks if your YAML document follows correct syntax rules and structure. It identifies errors like incorrect indentation, missing colons, unclosed quotes, and invalid characters, helping you fix configuration files before deployment.

How does this validator differ from the YAML formatter?

The validator focuses on checking syntax correctness and providing detailed error messages with line numbers. The formatter beautifies valid YAML with consistent indentation. Use the validator to find and fix errors, then use the formatter to clean up the structure.

Does this support schema validation?

Yes, the validator supports optional JSON schema validation. You can validate your YAML structure against a schema to ensure it has required fields and correct data types. This is useful for validating configuration files against expected formats.

What types of errors does it detect?

The validator detects syntax errors including incorrect indentation, missing or extra colons, unclosed quotes, invalid characters, malformed arrays and objects, and structural issues. Each error includes the line and column number where it occurred.

Is my data sent to a server?

No, all YAML validation happens in your browser. Your data never leaves your device, ensuring complete privacy and security for sensitive configuration files like Kubernetes manifests or CI/CD pipelines.

Can it validate Kubernetes YAML files?

Yes, this validator checks YAML syntax which works for Kubernetes manifests. For Kubernetes-specific validation (checking resource types, apiVersion, required fields), use our dedicated Kubernetes YAML Validator tool.

Does it support multi-document YAML?

The validator currently processes single YAML documents. If you have multiple documents separated by --- markers, validate each document separately for the most accurate error reporting.