How are numbers typed?

Whole numbers become Int and numbers with a decimal point become Float. Adjust manually if you need a different scalar.

What happens with null, empty arrays, or empty objects?

They map to a custom JSON scalar (or [JSON] for empty arrays), since their type can't be inferred. A `scalar JSON` declaration is added when used.

Yes. GraphQL fields are nullable by default, so no non-null (!) markers are added. Add them manually where a value is always required.

Is my JSON sent anywhere?

No. Conversion happens entirely in your browser; nothing is uploaded.

JSON to GraphQL Schema (SDL) Converter

Developer

Paste any JSON object or array and get GraphQL `type` definitions in Schema Definition Language with scalars mapped (String, Int, Float, Boolean, lists) and separate types for nested objects. Everything runs locally in your browser — your JSON is never uploaded.

—

Root type nameJSON input

GraphQL schema

type AutoGenerated {
  name: String
  age: Int
  active: Boolean
  tags: [String]
  meta: Meta
}

type Meta {
  id: String
}

How to use

Paste or type your JSON into the input box.
Optionally rename the root type (defaults to AutoGenerated).
Copy the generated SDL from the output box.

Frequently asked questions

How are numbers typed?: Whole numbers become Int and numbers with a decimal point become Float. Adjust manually if you need a different scalar.
What happens with null, empty arrays, or empty objects?: They map to a custom JSON scalar (or [JSON] for empty arrays), since their type can't be inferred. A `scalar JSON` declaration is added when used.
Are fields nullable?: Yes. GraphQL fields are nullable by default, so no non-null (!) markers are added. Add them manually where a value is always required.
Is my JSON sent anywhere?: No. Conversion happens entirely in your browser; nothing is uploaded.

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