JSON to YAML Converter

What JSON to YAML conversion does

JSON to YAML writes block YAML from a value produced by JSON.parse. YAML to JSON reads JSON (which is valid YAML 1.2) or a block YAML subset: indented maps, lists, quoted strings, and plain scalars. The conversion runs in the browser. Nothing is uploaded.

This is a converter, not a YAML 1.1 compatibility suite. Anchors, aliases, tags, merge keys, tabs for indent, | / > block scalars, and multi-document files starting with --- are rejected with a reason. Silently skipping those features would hide data.

How to use

1. Paste JSON or YAML.
2. Choose JSON to YAML, or YAML to JSON. Example loads a nested JSON object.
3. Copy output writes the result. Clear empties both boxes.

JSON to YAML fails the same way the JSON Validator fails: illegal JSON is not converted. YAML to JSON first tries JSON.parse, then the block parser.

Example

{
  "name": "Ada",
  "roles": ["admin", "editor"],
  "meta": {
    "active": true
  }
}

JSON to YAML should emit a name scalar, a roles list, and a nested meta map. YAML to JSON on that output should return the same types: a boolean stays a boolean, not the string "true".

When to use it

Use this for Magento/WordPress-adjacent config that is stored as YAML but produced as JSON, or the reverse. If you need a spreadsheet, use JSON to CSV instead. If you only need indentation of JSON, use the JSON Formatter.

Block lists use a hyphen at the item indent. A list item that starts a nested map can put the first key on the same line as the hyphen; following keys stay at the nested indent. That pattern is common in Compose-style files and is supported. Flow maps such as {a: 1} that are not JSON should be rewritten as block maps or as JSON.

Indent must be spaces. A tab is an error. Comments that occupy a whole line are skipped. A # after a value is treated as a comment only when it is spaced as value # comment. Keys that are not simple identifiers are JSON-quoted on output so they round-trip.

Round-trip JSON → YAML → JSON is the reliability target for objects, arrays, strings, numbers, booleans, and null. Exotic YAML that depends on merge keys or anchors will not pass. Prefer JSON if you need an unambiguous interchange format. If YAML to JSON succeeds, the output is indented JSON so you can read types; that indentation is presentation, not a second conversion. Review the types before you replace a production config file.

Limits

• Not a full YAML processor. Unsupported syntax errors instead of being ignored.
• Plain scalars follow a small set of booleans and numbers. Locale-specific YAML 1.1 booleans such as yes are accepted on input; JSON to YAML emits true/false/null.
• Strings that look like numbers or contain : are JSON-quoted so they round-trip.
• Traversal stops after 4000 nodes. Output is then cleared.

The format tradeoff is explained in JSON vs YAML.

Privacy

Parse and conversion run in this browser. Config files are not sent to YallaSolve for this tool.