Generate JSON Schema
Auto-generate JSON Schema from your data. Perfect for API documentation, validation rules, and TypeScript type generation. Supports Draft 7.
Generate Schema
Creates a JSON Schema based on the structure of your input data.
Pro tip: Provide sample data with various edge cases for more accurate schema generation.
📁 Drag and drop a .json file or paste JSON
How to Use JSON Formatter
- 1 Paste example JSON data (the more examples, the better)
- 2 Click "Generate Schema"
- 3 Review the generated JSON Schema
- 4 Adjust required fields if needed
- 5 Copy or download the schema
What You Get
Automatic JSON Schema generator. Analyzes your data to infer types, required fields, and constraints. Outputs JSON Schema Draft 7.
Input: {"name":"John","age":30}
Output: {"type":"object","properties":{"name":{"type":"string"},"age":{"type":"integer"}}}
How do I generate JSON Schema from data?
Paste sample JSON data and click Generate Schema. The tool analyzes your data to infer types, properties, and structure, outputting JSON Schema Draft 7.
What is JSON Schema used for?
JSON Schema is used for API documentation, data validation, form generation, and TypeScript type generation. It defines the structure and constraints of JSON data.
Which JSON Schema version is generated?
Draft 7, which is widely supported by validators like ajv, JSON Schema Validator, and most programming language libraries.
How are required fields determined?
Paste multiple examples - fields appearing in ALL examples are marked required. Single example means all fields are optional since we cannot infer which are required.
Can I use generated schema for API validation?
Yes. The output works with ajv (JavaScript), jsonschema (Python), and most JSON Schema validators. It is ready for production use.
How do I improve schema accuracy?
Paste multiple diverse examples. More examples help infer correct types (number vs string), optional fields, and array item types.
100% client-side processing - your JSON never leaves your browser.