Text Tools
YAML Formatter
Format and validate YAML with instant syntax checking.
Status
Valid
Paste your YAML above to format, validate, and copy the normalized output.
Text Tools
Format and validate YAML with instant syntax checking.
Status
Valid
Paste your YAML above to format, validate, and copy the normalized output.
YAML (YAML Ain't Markup Language) is a human-readable data serialization format widely used for configuration files in cloud infrastructure, CI/CD pipelines, and application settings. A YAML formatter automatically fixes spacing, indentation, and syntax to ensure your YAML is valid and readable.
Paste or upload your YAML code into the editor. The formatter parses your input, validates the syntax against YAML 1.2 specifications, then rebuilds the code with consistent indentation (typically 2 spaces per level) and proper key-value alignment. It highlights syntax errors like mismatched quotes, invalid nesting, or incorrect colons, making them easy to spot and fix.
| Input | Result | Notes |
|---|---|---|
| name: John Doe age:30 email: john@example.com address: street: 123 Main St city: Anytown | name: John Doe age: 30 email: john@example.com address: street: 123 Main St city: Anytown | Fixed spacing after colons and corrected nested 'city' indentation |
| services: web: image: nginx:latest ports: - '80:80' - '443:443' | services: web: image: nginx:latest ports: - '80:80' - '443:443' | Standardized 2-space indentation and aligned list items under 'ports' |
| database: host: localhost port: 5432 ssl: true | database: host: localhost port: 5432 ssl: true | Detected and fixed inconsistent indentation; 'port' should nest under 'database' |
JSON requires quotes around keys and strings, uses curly braces, and doesn't care about indentation. YAML uses indentation to define structure, rarely needs quotes, and is easier to read. Both represent the same data; YAML is often preferred for human-written configs.
Yes. Most YAML formatters handle files up to several megabytes. For extremely large files (10 MB+), process them in chunks or optimize using a command-line tool like yamllint or prettier with YAML plugins.
The formatter fixes syntax, but your logic or schema must still be correct. For Kubernetes, validate against schema using 'kubectl apply --dry-run=client'. For Ansible, use 'ansible-playbook --syntax-check'. Check tool-specific requirements.
This formatter handles YAML only. For conversion, use dedicated JSON-to-YAML or YAML-to-JSON tools. However, many online formatters include multi-format support—check if your provider offers both.
No. A good YAML formatter preserves comments. If comments are removed, use a different formatter or check your settings. Comments are valuable for documentation and should be retained.
Use command-line tools: yamllint, prettier --parser yaml, or Python's 'ruamel.yaml'. These integrate with CI/CD pipelines and pre-commit hooks to auto-format on every commit, eliminating manual steps.