YAML Validator – Free Online Tool

Example

server:
  host: localhost
  port: 3000

Valid YAML structure ✓. 5 lines, 3 keys, 0 comments

The validator confirms the YAML is structurally correct and shows document statistics.

How to Use YAML Validator

1. 1

   Enter YAML

   Paste your YAML content or upload a .yml file.

2. 2

   Review

   Validation runs automatically. Errors appear with line numbers.

3. 3

   Fix & Re-check

   Edit the YAML inline and see validation results update in real time.

What is YAML Validator?

The YAML Validator checks YAML syntax with line-level error reporting. It detects tabs (which YAML forbids), inconsistent indentation, unquoted keys with spaces, and structural issues. The editor shows line numbers with error highlighting for quick debugging.

Common Use Cases

• ✦Checking Kubernetes manifests before applying them
• ✦Validating CI/CD pipeline configuration files
• ✦Debugging YAML parsing errors in application configs

Frequently Asked Questions

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