JSON to GraphQL Schema Generator

What Is a JSON to GraphQL Schema Generator?

A JSON to GraphQL schema generator analyzes JSON data structures and produces corresponding GraphQL type definitions using the Schema Definition Language (SDL). GraphQL has become the query language of choice for modern APIs, providing strongly-typed schemas that define exactly what data clients can request. Creating these type definitions manually from existing JSON API responses is tedious, especially for complex data models with nested objects and arrays.

This tool examines each JSON property's value type and generates accurate GraphQL field types. Strings become String, integers become Int, floating-point numbers become Float, booleans become Boolean, arrays become list types with element type inference, and nested objects generate separate named types. The result is valid GraphQL SDL that can be used directly in Apollo Server, Hasura, AWS AppSync, or any GraphQL implementation. All generation runs locally in your browser with 100% client-side processing, keeping your data models private.

How to Generate GraphQL Schema from JSON

1. Paste your JSON data into the input panel. API response samples, database query results, or any JSON object representing your data model works.
2. Click Convert to analyze the JSON structure and generate GraphQL type definitions with correctly inferred field types.
3. Review the GraphQL SDL output showing type definitions with String, Int, Float, Boolean fields, list types for arrays, and separate types for nested objects.
4. Copy the GraphQL schema and paste into your schema.graphql file or pass to Apollo Server's type definitions. Add resolvers to complete your GraphQL API.

Why Use PinusX GraphQL Schema Generator?

Full-stack developers building GraphQL APIs with Apollo Server, Hasura, or AWS AppSync need type definitions that accurately represent their data models. Starting from existing JSON API responses or database records, PinusX generates GraphQL schemas instantly with 100% client-side processing — your data model samples, API response structures, and business entity definitions never leave your browser. This privacy-first approach protects proprietary data models, internal API contracts, and sensitive business logic from exposure to server-based generation tools.

Frequently Asked Questions

What GraphQL types are generated?

JSON strings map to GraphQL 'String', integers to 'Int', floating-point numbers to 'Float', booleans to 'Boolean', null to 'String' (nullable), arrays to list types like '[String]', and nested objects to separate named GraphQL types.

Does it handle arrays of objects?

Yes. Arrays containing objects generate a separate GraphQL type for the element and use list syntax. For example, an 'items' array of product objects produces a [RootItemsItem] field and a separate 'type RootItemsItem' definition.

Can I use this with Apollo Server?

Yes. The generated SDL is valid GraphQL schema language that works directly with Apollo Server's typeDefs parameter. You will need to add resolver functions for each type and field to complete your API implementation.

How are nested objects represented?

Nested JSON objects generate separate GraphQL type definitions. For example, a 'user' field containing an object with 'name' and 'email' properties produces a 'type RootUser { name: String, email: String }' definition referenced from the parent type.

Is my data model private?

Completely. All JSON to GraphQL schema generation runs locally in your browser. No data models, API structures, or JSON samples are sent to any server. Your proprietary schema designs remain entirely on your machine during generation.

Your data never leaves your browser. 100% client-side processing.