CodeBeautifyYAML Formatter & Beautifier
Format and beautify YAML online, fix indentation errors, and convert YAML to JSON or JSON to YAML. Collapse to compact flow-style YAML, or validate structure with clear error messages.
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What is YAML?
YAML ("YAML Ain't Markup Language") is a human-friendly data serialization format built around indentation rather than brackets or braces. It's the format of choice for configuration files across modern tooling — Docker Compose, Kubernetes manifests, GitHub Actions workflows, and Ansible playbooks are all written in YAML — because it's easier for people to read and write than the equivalent JSON.
YAML vs. JSON
- Structure — JSON uses
{}and[]; YAML uses indentation and dashes (-) for lists. - Comments — YAML supports
#comments; JSON has none. - Compatibility — every JSON document is valid YAML (in flow style), which is why this tool can convert either direction.
Example
| YAML | Equivalent JSON |
|---|---|
name: api | {"name":"api","port":8080,"tags":["web","prod"]} |
Frequently asked questions
How do I format YAML online?
Paste your YAML into the input box and click Beautify. The formatter fixes indentation instantly, so nested keys and lists line up correctly.
How do I beautify YAML?
Beautifying YAML re-indents block-style YAML with consistent spacing. Click Beautify, choose 2 or 4 spaces, and the beautifier reformats your YAML immediately.
Can every JSON document be converted to YAML?
Yes. YAML is a superset of JSON's data model, so any valid JSON document can be represented as YAML. The reverse isn't always true, since YAML supports features JSON doesn't, like comments, anchors/aliases, and multiple documents in one file.
What is 'flow style' in YAML?
Flow style writes YAML using JSON-like inline syntax, e.g. { key: value, list: [1, 2] }, instead of the usual indentation-based 'block style'. It's more compact and is what this tool's Minify button produces.