JSON schema generator

Infer a Draft 2020-12 JSON Schema from an example payload locally in your browser.

Runs locally in your browser. json park never receives this JSON text.

JSON input

{
  "account": {
    "id": "acc_123",
    "name": "Acme API",
    "active": true
  },
  "events": [
    { "type": "created", "attempt": 1 },
    { "type": "updated", "attempt": 2, "metadata": { "source": "web" } }
  ]
}

JSON Schema output

Common uses

Bootstrap a schema from real API payloads before refining it by hand.
Turn examples into a first contract shape for tests, docs, or CI checks.
Compare optional fields across repeated objects in arrays.

Details

Does schema generation upload my JSON?

No. The generator parses the payload and infers the schema in your browser through the local JSON worker.

How opinionated is the generated schema?

It stays conservative: primitive types, object properties, required keys, arrays, and anyOf for mixed examples. It does not guess formats, enums, examples, or defaults.