Free YAML Formatter & Validator Online
Pretty print, minify, and validate YAML documents with ease. Supports multi-document files and multiple formatting options. 100% client-side — your data stays private.
How to Use the YAML Formatter
- Paste your YAML into the input area above.
- Choose Pretty Print to format or Minify to compress.
- Set indentation to 2 or 4 spaces, toggle key sorting, and choose between block or flow style.
- Click "Process" or let it auto-process as you type.
- Check the status bar for validation results — errors highlight the problematic line.
- Use "Copy" or "Download" to save your formatted YAML.
Why Use This YAML Formatter
YAML is widely used for configuration files, CI/CD pipelines, and data serialization. This formatter makes your YAML files readable with proper indentation and structure.
It supports multi-document YAML (documents separated by ---), lets you switch between block and flow styles, and validates syntax in real-time so you catch errors before deploying your configuration.
Frequently Asked Questions
Yes. The tool handles YAML files with multiple documents separated by --- or ... markers correctly.
Block style uses indentation and newlines for structure (most common). Flow style uses braces and commas like JSON, e.g., {key: value} vs key: value.
No. All formatting and validation happens entirely in your browser. Your data never leaves your device.
Use Cases
Config File Formatting
Format messy YAML config files for applications, databases, and services to ensure proper indentation and structure.
Kubernetes Manifests
Clean up Kubernetes manifests with proper indentation and formatting for easier editing and deployment configuration.
CI/CD Pipeline Config
Pretty-print CI/CD pipeline configs for GitHub Actions, GitLab CI, and Jenkins to improve readability and maintenance.
Docker Compose Files
Organize Docker Compose files with consistent indentation and structure for multi-container application definitions.
YAML Standardization
Standardize YAML indentation across team projects to enforce consistent formatting conventions in shared repositories.