YAML Formatter & Beautifier — Format YAML Online [2026]
Format and beautify YAML with customizable indentation. Validates syntax, highlights errors with line numbers. Supports 2/4-space indent. Free, browser-based YAML pretty printer.
What is YAML Formatter?
How to Use YAML Formatter
Paste your YAML into the input area. Choose your preferred indentation (2 or 4 spaces). The tool formats the YAML automatically and displays the result. If there are syntax errors, they are shown with line numbers. Click "Copy" to copy the formatted output or "Download" to save it as a .yaml file.
How YAML Formatter Works
Common Use Cases
- Formatting messy Kubernetes or Docker Compose YAML files
- Standardizing indentation across YAML configuration files
- Validating YAML syntax before committing to version control
- Cleaning up auto-generated YAML from tools and APIs
- Reformatting GitHub Actions workflow files for readability
Frequently Asked Questions
What indentation options are available?▼
You can choose between 2 spaces (the most common YAML convention) and 4 spaces. The formatter applies the chosen indentation consistently throughout the document.
Does it validate YAML syntax?▼
Yes. If your YAML contains syntax errors like incorrect indentation, invalid characters, or duplicate keys, the tool will show an error message with the line number where the problem was found.
Does it preserve comments?▼
The formatter parses YAML into a data structure and re-serializes it, so comments are not preserved. If you need to keep comments, consider only using it for validation rather than formatting.
Is my data safe?▼
Yes. All formatting happens in your browser. No data is sent to any server.