JSON Schema Generator

12 tools

Infer a JSON Schema from a sample.

Runs in your browser — your files and text stay on your device

Infer a JSON Schema from a sample document. The result is a starting point: a single sample can't show which fields are optional or what values are allowed, so tighten the schema by hand. It runs locally in your browser.

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Sample JSON

JSON Schema

{
  "$schema": "http://json-schema.org/draft-07/schema#",
  "type": "object",
  "properties": {
    "id": {
      "type": "integer"
    },
    "name": {
      "type": "string"
    },
    "active": {
      "type": "boolean"
    },
    "roles": {
      "type": "array",
      "items": {
        "type": "string"
      }
    }
  },
  "required": [
    "id",
    "name",
    "active",
    "roles"
  ]
}

How to use this tool

1Paste a sample JSON payload.
2A draft-07 JSON Schema is inferred automatically.
3Copy it, or test it against other payloads in the Schema Validator tab.

Frequently asked questions

Does it mark every field as required?

Yes — since it only sees one sample, every key present is assumed required. Edit the generated schema's "required" array by hand to make fields optional.

Is my JSON uploaded anywhere?

No, the schema is generated entirely in your browser.

Guides

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