JSON to YAML Converter

Instantly convert JSON to clean, idiomatic block-style YAML — all in your browser, no server, no signup.

How JSON to YAML Conversion Works

{"name":"Alice","roles":["admin","user"],"active":true}

name: Alice
roles:
  - admin
  - user
active: true

Frequently Asked Questions

How does JSON to YAML conversion work?

The converter parses your JSON using the browser's native JSON.parse(), then serializes the resulting JavaScript object to YAML using js-yaml v5 with block-style output. JSON objects become YAML mappings, arrays become sequences, and all scalar types (strings, numbers, booleans, null) map directly.

Is YAML a superset of JSON?

Yes. Every valid JSON document is also valid YAML 1.2. This means you can paste JSON directly into a YAML parser and it will work. However, the converted output uses idiomatic YAML block style, which is more readable than the equivalent JSON representation.

When should I use YAML instead of JSON?

YAML is better for human-authored files like configuration (Docker Compose, Kubernetes, GitHub Actions, Ansible) because it supports comments, multi-line strings, and anchors. JSON is better for machine-to-machine data exchange — APIs, webhooks, and storage — because every language has a fast native JSON parser.

Is my data sent to a server?

No. The conversion runs entirely in your browser using js-yaml v5. Your data never leaves your machine.

What happens to JSON null values in YAML?

JSON null becomes YAML null or the tilde ~ in YAML output. Both are valid YAML representations of a null value. js-yaml serializes null as null by default.

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