Why does indentation matter in YAML?

YAML uses indentation (spaces) to define structure and nesting, similar to Python. Incorrect indentation changes the meaning of your data. Always use spaces, never tabs.

Can I use tabs for indentation?

No! YAML specification requires spaces for indentation. Tabs will cause syntax errors. Use 2 or 4 spaces consistently throughout your file.

What's the difference between YAML and JSON?

YAML is more human-readable with less syntax (no braces/brackets). It supports comments and multi-line strings. JSON is stricter and more verbose but easier for machines to parse.

Why convert YAML to JSON?

Converting to JSON helps you visualize the data structure, debug complex configurations, and understand how YAML parsers interpret your file. It's also useful for API testing.

Does this support multi-document YAML?

Yes! The validator supports YAML files with multiple documents separated by `---`. Each document is validated independently.

YAML Validator

YAML Validator Overview

Validate YAML syntax and convert to JSON

YAML Validator is a syntax checker and JSON converter for YAML (YAML Ain't Markup Language) files, the human-readable data serialization format used extensively in configuration files. YAML is the standard for Docker Compose, Kubernetes manifests, GitHub Actions workflows, Ansible playbooks, and many modern DevOps tools. Unlike JSON, YAML uses indentation (spaces, not tabs) to denote structure, making it prone to subtle syntax errors that can break deployments. This validator checks for common YAML issues including indentation errors, invalid syntax, improper use of colons and dashes, and malformed multi-line strings. When your YAML is valid, the tool automatically converts it to JSON, helping you understand the data structure and debug complex configurations. The validator provides clear error messages with context, making it easy to identify and fix issues. YAML validation is critical for DevOps engineers deploying containers, developers writing CI/CD pipelines, system administrators managing configuration, and anyone working with YAML-based tools. All validation happens client-side in your browser for complete privacy.

How to Use YAML Validator

Paste your YAML content into the input textarea
Click 'Load Sample' to see example YAML structure
Click 'Validate YAML' to check syntax
Review validation results: Valid (green) or Invalid (red)
If invalid, check the error message for details
For valid YAML, view the JSON conversion output
Copy the JSON output to clipboard if needed

Frequently Asked Questions

Why does indentation matter in YAML?: YAML uses indentation (spaces) to define structure and nesting, similar to Python. Incorrect indentation changes the meaning of your data. Always use spaces, never tabs.
Can I use tabs for indentation?: No! YAML specification requires spaces for indentation. Tabs will cause syntax errors. Use 2 or 4 spaces consistently throughout your file.
What's the difference between YAML and JSON?: YAML is more human-readable with less syntax (no braces/brackets). It supports comments and multi-line strings. JSON is stricter and more verbose but easier for machines to parse.
Why convert YAML to JSON?: Converting to JSON helps you visualize the data structure, debug complex configurations, and understand how YAML parsers interpret your file. It's also useful for API testing.
Does this support multi-document YAML?: Yes! The validator supports YAML files with multiple documents separated by `---`. Each document is validated independently.

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