YAML Validator & Formatter

Indent:

YAML Input

Output

Paste YAML on the left and click Format or Convert

Powerful YAML Tools

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Instant Validation

Validate YAML syntax as you type. Get detailed error messages with exact line and column numbers, helping you quickly identify and fix syntax issues.

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Format & Beautify

Beautify messy YAML with proper indentation and formatting. Choose between 2 or 4 space indentation to match your project's style guide.

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YAML ⇄ JSON

Convert between YAML and JSON formats instantly. Perfect for API development, configuration management, and data transformation workflows.

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Copy & Download

Copy formatted output to clipboard or download as .yaml, .yml, or .json files. Your data never leaves your browser for complete privacy.

About YAML Validation and Formatting

YAML (YAML Ain't Markup Language) is a human-readable data serialization format commonly used for configuration files, data exchange, and infrastructure-as-code tools like Kubernetes, Ansible, and Docker Compose. Unlike JSON, YAML uses indentation and whitespace to denote structure, making it easy to read but also prone to syntax errors from incorrect spacing or tabs.

Why Validate YAML?

YAML's sensitivity to whitespace means that even a single misplaced space or tab can cause parsing errors that are difficult to spot visually. Our validator instantly checks your YAML syntax and provides precise error messages showing exactly where problems occur. This is invaluable when working with complex configuration files or debugging deployment issues in CI/CD pipelines.

Formatting and Beautification

Messy or inconsistently indented YAML files are hard to maintain and can lead to errors. Our formatter restructures your YAML with clean, consistent indentation, making it easier for teams to collaborate and maintain configuration files. You can choose between 2-space or 4-space indentation to match your project's coding standards.

YAML to JSON Conversion

Many APIs and tools accept JSON but configuration files are often written in YAML for readability. Our converter seamlessly translates between YAML and JSON, preserving data types and structure. This is particularly useful when migrating configurations, testing API payloads, or working with tools that support only one format.

Common Use Cases

Kubernetes Manifests: Validate deployment, service, and ingress YAML files before applying them to your cluster.
CI/CD Pipelines: Check GitHub Actions, GitLab CI, or CircleCI configuration files for syntax errors.
Docker Compose: Validate docker-compose.yml files and ensure proper service configuration.
Ansible Playbooks: Verify playbook syntax before running automation tasks.
Configuration Management: Format application config files for consistency across environments.

Frequently Asked Questions

How do I validate YAML syntax? ▼

Paste your YAML content into the input area and the validator will instantly check for syntax errors. If errors are found, you'll see detailed messages with line and column numbers indicating exactly where the problem is.

Can this tool format messy YAML? ▼

Yes, the formatter can beautify YAML with proper indentation. You can configure the indent size (2 or 4 spaces) and the tool will restructure your YAML with consistent formatting, making it easier to read and maintain.

How do I convert YAML to JSON? ▼

After pasting your YAML, click the 'Convert to JSON' button. The tool will parse the YAML structure and output equivalent JSON with proper formatting and syntax highlighting.

Can I convert JSON to YAML? ▼

Yes, paste valid JSON into the input area and click 'Convert to YAML'. The tool will convert the JSON structure to clean, properly indented YAML format.

What YAML features are supported? ▼

The validator supports YAML 1.2 features including maps (objects), sequences (arrays), strings, numbers, booleans, null values, multiline strings (literal and folded), comments, anchors and aliases, and nested structures.

Does the validator show error locations? ▼

Yes, when syntax errors are detected, the validator displays detailed error messages showing the exact line number and column where the error occurred, along with a description of the problem.

Can I download the formatted output? ▼

Yes, you can copy the formatted YAML to clipboard or download it as a .yaml or .yml file. For JSON conversions, you can download as a .json file.

Is my YAML data secure? ▼

Yes, all validation and formatting happens entirely in your browser. Your YAML data is never sent to any server, stored, or logged. The tool operates 100% client-side for complete privacy.

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