toolkit

JSON Schema Generator

Runs in browser

Generate JSON Schema from JSON data

How to Use

Paste JSON object or array. Configure options for required props/examples.

You will see:

  • Generated Draft-07 Schema
  • Inferred Types & Structures
  • Live Preview
  • Copy-ready Output
JSON Schema

No schema generated

Enter JSON to generate schema

About JSON Schema Generator

JSON Schema Generator is a powerful developer tool that automatically creates Draft-07 JSON Schemas from your JSON data. It recursively analyzes your data structure to produce accurate validation rules, type definitions, and structural constraints, saving you hours of manual schema writing.

Key Features

Smart Inference

Recursively detects data types (String, Integer, Number, Boolean, Array, Object) and identifies nested structures to build a comprehensive schema hierarchy.

Draft-07 Compatible

Generates standard Draft-07 schemas which are widely supported by validators across Node.js, Python, Go, Java, and .NET ecosystems.

Customizable Output

Control how strict your schema is. Easily toggle whether all detected properties should be marked as required or kept optional.

Common Use Cases

  • API Documentation: Generate schemas for OpenAPI/Swagger definitions
  • Data Validation: Create rules to validate incoming HTTP requests or database entries
  • Frontend Forms: Use schemas to auto-generate form inputs using libraries like react-jsonschema-form
  • Testing: Verify that API responses match the expected format during automated tests

Frequently Asked Questions

How are arrays handled?

The generator inspects the first item in an array to determine the schema for all items (`items` keyword). This covers the most common case of uniform lists. Handling mixed-type arrays (`oneOf` / `anyOf`) is planned for future updates.

What happens with null values?

Null values are typed as "type": "null". If you need nullable fields (e.g. string OR null), you might need to manually adjust the schema to use ["string", "null"].

Further Reading