YAML Formatter

This free online YAML formatter formats, minifies, and validates YAML, making it easier to read and debug — in one click.

All tools on this site run entirely in your browser locally. No data is uploaded to any server.

Features:

• Format YAML: Auto-format indentation (2 spaces), fix nesting structure, support folding/expanding nodes
• Keep comments: When enabled, original comments are preserved (including trailing comments); the setting is remembered; in compact mode, comments are dropped
• Compact mode: Converts objects/arrays to flow-style (inline) format, smaller size for comparison
• Syntax validation: Real-time syntax error hints after input, helps locate indentation or colon issues
• YAML validation: Click the validate button to check for syntax errors, tab indentation, and duplicate keys. It also flags boolean spelling errors (e.g., "tru"/"flase"), trailing whitespace, excessively long lines, comment formatting issues, and trailing blank lines.
• Local files: Drag and drop or select local YAML/YML files
• Real-time processing: Auto-formats on input, or manually click the format button to reformat
• Export results: One-click copy, save as file, with search, jump to line and fullscreen view

Common uses:

• Formatting and beautifying YAML config files (e.g., Docker Compose, Kubernetes, Spring Boot)
• Troubleshooting YAML indentation or syntax issues and quickly locating the errors
• Comparing config differences across versions; compact mode is ideal for diff
• Organizing Ansible Playbooks, GitHub Actions and other YAML script files
• Converting JSON results to YAML for use in configuration management tools