JSON ↔ YAML converter

This converter parses one format into an in-memory data structure and serializes it as the other. JSON is parsed with the native JSON.parse; YAML is parsed with js-yaml using its JSON-compatible schema, which keeps type coercion predictable. Because both formats describe the same underlying model — maps, sequences, strings, numbers, booleans, null — the conversion is lossless for data, though format-only details like comments, blank lines, and quote style are not carried across.

It runs entirely in your browser. Kubernetes manifests, CI pipeline definitions, and application config with secrets in them can be converted here without leaving the page.

• Turning a JSON API response into YAML to paste into a config file.
• Converting a Docker Compose or GitHub Actions YAML file to JSON so a script can read it with a standard parser.
• Checking whether a hand-written YAML file parses to the structure you expect by viewing it as JSON.
• Normalising a YAML file's formatting by round-tripping it through the tool.

Input (JSON):

{"service":"web","replicas":3,"env":[{"name":"LOG_LEVEL","value":"info"}],"tls":true}

Output (YAML):

service: web
replicas: 3
env:
  - name: LOG_LEVEL
    value: info
tls: true

Converting that YAML back to JSON with 2-space indent returns the original object exactly. Now change value: info to value: yes in the YAML and convert to JSON: you get "value": true, because bare yes is a YAML boolean. Quote it as value: "yes" and it stays the string "yes".

• Comments and layout are not preserved in either direction.
• YAML-only types such as !!timestamp, !!binary, and custom tags are not represented in JSON and will error or be stringified.
• Multi-document YAML (files separated by ---) is not supported; convert one document at a time.
• Key order is preserved as written. JSON object keys and YAML mapping keys both keep insertion order here.
• Very deep or very large documents are converted synchronously and will briefly block the tab.
• This is a syntax converter, not a schema or policy validator — it will happily convert a manifest that your cluster would reject.