YAML Formatter
Format and validate YAML documents with consistent indentation.
About this tool
Format and validate YAML documents with consistent indentation. Useful when reviewing API responses, cleaning config before commit, or sharing readable snippets in docs and PRs.
Paste a YAML document (compact, messy, or partially indented). Click Format to normalize indentation and map/list structure. Example — Normalize a small service config: try `name: api port: 8080 flags: [beta, metrics]` and expect something like `name: api port: 8080 flags: - beta - metrics`.
Formatting re-dumps parsed YAML — comments and some stylistic anchors may be dropped. See also: YAML to JSON, JSON to YAML, and JSON Formatter. Runs in your browser — nothing you paste gets uploaded.
How to use
- Paste a YAML document (compact, messy, or partially indented).
- Click Format to normalize indentation and map/list structure.
- Scan the Output for unexpected type coercations (yes/no, bare numbers).
- Copy the cleaned YAML into config files or convert onward with YAML to JSON.
Example
Normalize a small service config
Input
name: api port: 8080 flags: [beta, metrics]
Output
name: api port: 8080 flags: - beta - metrics
Limitations
- Formatting re-dumps parsed YAML — comments and some stylistic anchors may be dropped.
- Custom tags and merge keys may not round-trip exactly as authored.
- This is not a Kubernetes schema validator — it only checks YAML syntax/structure.
Related guides
1Related tools
3Frequently asked questions
What does the YAML Formatter do?
Format and validate YAML documents with consistent indentation. Runs in your browser — no install, no account.
How do I use the YAML Formatter?
Paste a YAML document (compact, messy, or partially indented). Click Format to normalize indentation and map/list structure. Scan the Output for unexpected type coercations (yes/no, bare numbers). Copy the cleaned YAML into config files or convert onward with YAML to JSON.
Is the YAML Formatter free?
Yes. No signup, no usage limits, no paywall.
Does the YAML Formatter upload my data?
No. Processing happens locally in JavaScript. Your input is not uploaded, stored, or logged.
What are the limitations of the YAML Formatter?
Formatting re-dumps parsed YAML — comments and some stylistic anchors may be dropped. Custom tags and merge keys may not round-trip exactly as authored. This is not a Kubernetes schema validator — it only checks YAML syntax/structure.