GraphQL to TypeScript Converter

Q: How are GraphQL enums converted?

GraphQL enums become TypeScript enum declarations or union types. Each enum value is preserved with string values matching the GraphQL name.

Q: What GraphQL scalars are supported?

Built-in GraphQL scalars map as follows: String→string, Int→number, Float→number, Boolean→boolean, ID→string. Custom scalars default to 'unknown' or 'any'.

Q: Is this different from graphql-code-generator?

graphql-code-generator is a CLI tool for production use with config files and plugins. This converter is a quick online tool for developers who need to inspect or prototype TypeScript types from a GraphQL schema without setting up a full codegen pipeline.

Convert GraphQL schema SDL to TypeScript interfaces and types with AI — free, no login required.

Working with a GraphQL API in TypeScript? Paste your schema types and get the equivalent TypeScript interfaces — with correct nullability, enums, and array types.

Paste your code, then click Convert

TypeScript

How to use this tool?

This online converter harnesses AI to translate GraphQL schema SDL to TypeScript types and interfaces. Follow these steps:

Type or paste your GraphQL schema (type definitions, inputs, enums) into the input box.
Click the "Convert" button to generate equivalent TypeScript types.
View the TypeScript interfaces and types in the output box, ready to use.

Example: Simple Function

GraphQL

type User {
  id: ID!
  name: String!
  email: String
  role: Role!
  posts: [Post!]!
}

enum Role {
  ADMIN
  USER
}

TypeScript

export enum Role {
  ADMIN = "ADMIN",
  USER = "USER",
}

export interface User {
  id: string;
  name: string;
  email: string | null;
  role: Role;
  posts: Post[];
}

How to Convert GraphQL schema SDL to TypeScript

GraphQL schemas define every type, query, mutation, and subscription in your API. Using GraphQL responses in TypeScript without generated types means using any for all query results — losing all type safety and IDE support.

The GraphQL to TypeScript converter generates TypeScript interfaces and types from your GraphQL schema SDL. Paste your schema and get typed interfaces for every GraphQL type, input, enum, and union.

Why Use a GraphQL schema SDL to TypeScript Converter?

→Type-check GraphQL query responses without setting up a full code generation pipeline
→Generate TypeScript interfaces from GraphQL schema for use in Apollo, urql, or fetch
→Keep TypeScript types aligned with GraphQL schema changes
→Document GraphQL type shapes as TypeScript interfaces for team reference

What the GraphQL to TypeScript Converter Handles

GraphQL type to TS interface

Input types to TS interfaces

Enum types to TS enums

Union types to TS union types

Interface types (GraphQL)

Scalar type mapping

Non-null to required fields

Nullable to optional fields

List types to arrays

Fragment types

Query and Mutation return types

Subscription types

Frequently Asked Questions

How are non-null fields handled?

GraphQL non-null fields (Type!) become required TypeScript properties. Nullable fields (Type) become 'Type | null' — matching GraphQL's null semantics exactly.

How are GraphQL enums converted?

GraphQL enums become TypeScript enum declarations. Each enum value is preserved with a string value matching the GraphQL name.

Are GraphQL input types supported?

Yes. GraphQL 'input' types are converted to TypeScript interfaces with an 'Input' suffix to distinguish them from output types.

What GraphQL scalars are supported?

String→string, Int→number, Float→number, Boolean→boolean, ID→string. Custom scalars default to 'unknown'.

Is this different from graphql-code-generator?

graphql-code-generator is a CLI tool for production use. This is a quick online converter for prototyping or inspecting types — no config, no install, just paste and convert.

Are list types converted correctly?

Yes. GraphQL list types ([Type]) become TypeScript arrays (Type[]). Non-null list items ([Type!]) become non-nullable arrays.

How do I generate TypeScript types from a GraphQL schema?

Paste your GraphQL SDL (schema definition language) into the converter. The tool generates TypeScript interfaces matching each GraphQL type, input, enum, and union. For automated generation in a project, use graphql-codegen.

What is GraphQL SDL?

GraphQL SDL (Schema Definition Language) is the language used to define GraphQL schemas. It describes types, fields, queries, mutations, and subscriptions: type User { id: ID! name: String! email: String }.

How are GraphQL nullable vs non-null fields converted?

GraphQL fields are nullable by default. Non-null fields (marked with !) become required TypeScript properties. Nullable fields become optional (field?: Type) or typed with undefined.

What is the difference between GraphQL interfaces and TypeScript interfaces?

GraphQL interfaces define shared fields that implementing types must include. TypeScript interfaces define object shapes for type checking. Both concepts translate well — a GraphQL interface becomes a TypeScript interface that implementing GraphQL types extend.

How are GraphQL enums converted to TypeScript?

GraphQL enum types convert to TypeScript enum declarations or string union types: type Status = "ACTIVE" | "INACTIVE" | "PENDING". Both representations are valid; string unions are generally preferred in modern TypeScript.

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