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Convert JSON to
GraphQL Schema
Instantly

Paste any JSON object and get clean GraphQL SDL types in seconds. Free, accurate, and 100% private — your data never leaves your browser.

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  • Nested objects & arrays supported
  • Monaco editor with syntax highlighting
  • Zero server — 100% in your browser
schema.graphql
JSON Input
{
  "user": {
    "id": 1,
    "name": "Ada",
    "isPremium": true,
    "score": 98.6,
    "address": {
      "city": "London"
    }
  }
}
GraphQL SDL
type Address {
  city: String
}

type User {
  id: Int
  name: String
  isPremium: Boolean
  score: Float
  address: Address
}

type Query {
  data: RootType
}

Interactive Converter

JSON Inputeditable
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GraphQL SDL Outputread-only
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3 types generated
🔒 100% Secure — stays in browser

Generated schemas are provided as reference. Always validate and test before using in production.

Why developers choose this tool

Built for speed, accuracy, and complete privacy.

Instant Conversion

Results appear as you type with a 300ms debounce. No button press required — the schema updates live as your JSON evolves.

Nested Type Support

Recursively generates named GraphQL types for deeply nested JSON objects. Arrays of objects become typed list fields automatically.

100% Private

Everything runs in your browser. There is no server, no data upload, and no logging. Your JSON stays entirely on your machine.

Frequently Asked Questions

Everything you need to know about converting data to GraphQL schemas.

How do I convert JSON to a GraphQL schema?

Paste your data into the left editor pane. The tool instantly generates the corresponding GraphQL SDL (Schema Definition Language) in the right pane, with correctly inferred scalar types and nested object structures. No sign-up or server required.

What GraphQL scalar types do JSON values map to?

JSON strings map to String, integers to Int, floating-point numbers to Float, booleans to Boolean, and null values to a nullable String field. Nested objects become named types, and arrays become list fields.

Can I generate GraphQL types from nested JSON?

Yes. The tool recursively processes nested structures, creating a separate type for each nested object with PascalCase names derived from the key. Arrays of objects produce a list field with the inferred item type.

Is my JSON data secure when using this tool?

Completely. Everything runs in your browser — your data is never sent to any server. No information is stored, logged, or transmitted anywhere.

What is GraphQL SDL?

SDL (Schema Definition Language) is the human-readable syntax for defining a GraphQL schema. It describes types, fields, queries, mutations, and subscriptions. SDL files use the .graphql extension and are the standard way to define APIs.

Can I make all fields non-null in the generated schema?

Yes. Enable the Non-null by default toggle in the toolbar. This appends ! to all fields whose JSON value is not null, marking them as required in the GraphQL schema.

What is JSON introspection to GraphQL SDL?

It's the process of analyzing an object's structure and automatically generating a matching GraphQL schema. This tool reads your data shape and outputs ready-to-use type definitions.

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