YAML Formatter
Format and validate YAML for config files, Kubernetes manifests, Docker Compose, and CI pipelines. Normalizes indentation and surfaces syntax errors.
How to use the yaml formatter
Paste YAML into the input box and press Format. The tool re-emits a clean indented version using two-space indentation — useful for normalizing files that mix tabs and spaces, or for catching syntax errors before committing.
Formula & explanation
Round-trip through our YAML parser: parseYaml(input) produces a JS value, then toYaml() serializes it back out. Any syntax error surfaces during parsing.
Examples
Input with inconsistent spacing or tabs becomes output with uniform two-space indent. Lists, nested mappings, scalars, and booleans are normalized.
Frequently asked questions
- Does this support the full YAML spec?
- No — we parse a safe subset (no anchors/aliases, no flow style, no multiline scalars). It handles the parts of YAML that real config files actually use (Compose, Kubernetes manifests, GitHub Actions, Ansible).
- Will it preserve comments?
- No. YAML comments are stripped during parsing because they aren't part of the parsed value. If you need to preserve comments, format with a full-fidelity tool like yamllint.
- Does this validate against a schema?
- Just syntax. For schema validation (e.g. Kubernetes resource schemas), use a dedicated linter. For LLM tool/function schemas, see our LLM JSON Schema Validator.
- Does this send my YAML to a server?
- No. Parsing and formatting happen entirely in your browser.
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