Free Online JSON Schema Generator
Generate JSON Schema from your JSON data. Supports draft-04, draft-07, and 2020-12. Perfect for API documentation and data validation.
data_object Input JSON
code Generated JSON Schema
Click Generate Schema to create a JSON Schema from your JSON input.
Key Features
Multi-Version Support
Generate schemas in draft-04, draft-07, or 2020-12 format.
Accurate Type Detection
Automatically detects object, array, string, number, boolean, and null types.
Nested Object Handling
Properly generates schema for deeply nested JSON structures with $defs support.
Privacy Safe
All processing runs locally in your browser. No data upload needed.
Frequently Asked Questions
Getting Started
What is a JSON Schema?
JSON Schema is a vocabulary that allows you to annotate and validate JSON documents. It describes the structure, constraints, and data types of JSON data.
What schema versions are supported?
The tool supports draft-04, draft-07, and 2020-12. Draft-07 is recommended for most use cases.
Features & Usage
Can I generate schema from any JSON?
Yes. The tool accepts any valid JSON and generates an appropriate schema. Complex nested objects and arrays are handled automatically.
Is the generation lossless?
The generated schema accurately represents the structure of your input JSON. However, since JSON alone cannot express constraints like minimum/maximum values or regex patterns, those will not be included.
How do I use the generated schema?
The generated schema can be used with any JSON Schema validator library in your programming language of choice to validate JSON data against the expected structure.
Troubleshooting
What if my input is not valid JSON?
The tool will display an error message indicating the JSON parse error. Please check your JSON syntax and try again.
Can I use this tool offline?
Yes. Once you have visited the page, all functionality works offline thanks to local processing.
Is my data safe when using this tool?
Yes. All processing happens locally in your browser. Your JSON data never leaves your device. No upload is needed.