JSON Schema Generator
Generate a JSON Schema (draft 2020-12) from any JSON object. Supports nested objects and arrays.
JSON Input
Generated JSON Schema
Paste JSON to generate schema
JSON Schema Generator
Paste any JSON document and get a complete JSON Schema with $schema, $id, title, type definitions, required arrays, and additionalProperties constraints — ready for use in validators like Ajv, jsonschema, or API gateways.
Frequently Asked Questions
- What is JSON Schema?
- JSON Schema is a vocabulary that allows you to annotate and validate JSON documents. It is used to define the structure, data types, and constraints of JSON data — commonly used in APIs, form validation, and configuration files.
- Which JSON Schema draft does this tool target?
- The generator outputs schemas compatible with JSON Schema Draft 2020-12, the latest published specification.
- What does additionalProperties: false mean?
- This keyword causes validators to reject JSON objects that contain properties not defined in the schema. The generator adds this by default for strict validation.
- Is my JSON data uploaded anywhere?
- No. Schema generation runs entirely in JavaScript within your browser. Your JSON content never leaves your device.