FreeDev Tools

JSON to GraphQL Schema

Generate GraphQL type definitions from a JSON object — nested objects become nested types.

Runs locally in your browser. Your input is not uploaded.

How to Use

  1. 1

    Paste sample JSON

    Paste a representative object, such as one item from your API.

  2. 2

    Review the types

    Check nullability and Int vs Float inference against your actual data contract.

  3. 3

    Copy the SDL

    Paste into your schema.graphql and rename Root to your entity name.

Frequently Asked Questions

GraphQL SDL type definitions inferred from a JSON sample — scalar fields (String, Int, Float, Boolean), list types, and nested object types, with non-null markers on fields present in the sample.

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