Paste any JSON and get a valid JSON Schema automatically.
JSON Schema Generator is a free online tool that automatically creates a valid JSON Schema from any JSON data you provide. It analyzes the structure, data types, and patterns in your JSON to produce a comprehensive schema that can be used for validation, documentation, and API contract definition. The generator detects all JSON data types including strings, numbers, integers, booleans, arrays, objects, and null values. It identifies string formats like email addresses, URLs, dates, and UUIDs. For arrays, it determines the item types and creates appropriate schema definitions. Nested objects are recursively analyzed to produce complete schema hierarchies. JSON Schema is a powerful standard for describing the structure of JSON data. It's used extensively in API development for request/response validation, in configuration management for ensuring correct settings, and in documentation for clearly communicating data structures to other developers. Everything runs entirely in your browser. Your JSON data is never sent to any server, ensuring privacy for sensitive data structures, API contracts, and proprietary data models. There are no file size limits, no usage restrictions, and no account required. Common use cases include generating validation schemas for REST APIs, creating documentation for data interchange formats, building form validation rules from sample data, defining database document schemas for MongoDB or similar databases, and establishing data contracts between microservices. For related functionality, use the JSON Formatter to beautify and validate your JSON data before generating a schema, or the Schema Markup Generator for creating structured data for search engines.