JSON to GraphQL Converter - Generate GraphQL Types Online

🔷 JSON to GraphQL Schema

Automatically generate GraphQL type definitions from JSON sample. Perfect for GraphQL API development.

📝 Input JSON:
📤 Output GraphQL Schema:
// GraphQL types will appear here...
Types: 0
Fields: 0
Nested: 0
💡 Example JSON Samples:
👤 User Object
Simple user with basic fields
🛍️ Product with Nested
Product with nested category and tags
📡 API Response
Typical API response structure

Online JSON to GraphQL Converter: Rapidly Generate GQL Types

Modernize your API development with our JSON to GraphQL tool. Manually writing GraphQL Type Definitions (SDL) can be time-consuming, especially when dealing with deeply nested JSON objects from legacy REST APIs. This tool allows you to paste any JSON sample and instantly receive a clean, structured GraphQL, including types, nested objects, and arrays.

Why Convert JSON to GraphQL?

GraphQL is the modern standard for flexible and efficient APIs, but defining the schema is the first—and often most tedious—step.

Accelerate Your Development Workflow

Instead of manually mapping every field from a JSON response to a GraphQL type, let our tool do it for you. This is perfect for developers who are building a GraphQL wrapper around an existing REST API or initializing a new Apollo or Relay project.

Ensure Schema Accuracy

Human error during manual schema writing can lead to mismatched types and runtime errors. By generating your schema directly from real data samples, you ensure that your Int, String, Boolean, and Float types are correctly identified from the start.

Key Features of Our JSON to GraphQL Tool

Our converter is designed to handle the complexities of the GraphQL Schema Definition Language (SDL).

1. Intelligent Type Inference

Our engine analyzes your JSON values to determine the most appropriate GraphQL scalar types:

  • "text" → String

  • 123 → Int

  • 12.34 → Float

  • true → Boolean

  • null → String (Default)

2. Recursive Nested Object Support

If your JSON data contains nested objects, the converter automatically creates additional type blocks. This ensures that your schema remains modular and follows the graph structure that GraphQL is known for.

3. Array to List Mapping

Our tool identifies arrays in your JSON and maps them to GraphQL List types (e.g., [User]). It also scans the elements of the array to ensure the inner type is consistent.

How to Convert JSON to GraphQL

  1. Paste your JSON: Insert your raw JSON response or object into the input editor.

  2. Naming: (Optional) Give your root type a name, such as User, Product, or QueryResponse.

  3. Instant Conversion: The GraphQL Definition (SDL) appears immediately in the output window.

  4. Implement: Copy the generated types and paste them into your schema file or your typeDefs constant.

Technical Insights: Mapping Logic

Handling Required Fields

By default, fields in GraphQL are nullable. However, if you are using a JSON Schema as input or if you want strict validation, you can manually add the ! (Non-Null) operator to the generated code where necessary.

From Objects to Inputs

While this tool primarily generates type definitions for queries, the same structure can be easily adapted into input types for your GraphQL mutations by simply changing the keyword from type to input.

Frequently Asked Questions (FAQ)

Does this tool support JSON Schema?

Yes. You can paste a standard JSON Schema, and the converter will use the property definitions to build your GraphQL types.

Is it compatible with Apollo Server?

Absolutely. The output is standard GraphQL SDL, which is fully compatible with Apollo, Yoga, Relay, and any other GraphQL-compliant engine.

Is my data secure?

Yes. All processing happens 100% in your browser. We do not store or transmit your JSON data to any external servers, keeping your API structures confidential.