Generate Kotlin Data Classes from API Response

Generate Kotlin data classes with kotlinx.serialization annotations from a typical REST API JSON response. Paste your API output and get typed Kotlin code.

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Output

Root name

Import path

JSON Input

TypeScript Output

// Generated by DevBento — json-to-typescript
interface RootAddress {
  street: string;
  city: string;
  zip: string;
}

interface RootPostsItem {
  title: string;
  likes?: number;
}

interface Root {
  id: number;
  name: string;
  email: string;
  isActive: boolean;
  roles: string[];
  address: RootAddress;
  posts: RootPostsItem[];
}

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Generate Kotlin Data Classes from API Response

This example generates Kotlin data classes with kotlinx.serialization annotations from a typical REST API response. The pre-filled JSON represents a user object with nested address, array of roles, and array of post objects. Switch to Kotlin mode to see the generated classes.

What You Get

The tool produces:

A root Root data class with @Serializable and @SerialName annotations
RootData class for the nested address object
RootPostsItem class for array items
@SerialName("key") attributes on every property
camelCase property names following Kotlin conventions
Nullable types (T?) with null defaults for optional fields
Kotlin type mappings: String, Long, Double, Boolean, List<String>

How to Use

The example loads with a sample API response and Kotlin mode pre-selected
Inspect the generated Kotlin data classes and their annotations
Copy the classes and paste them into your Kotlin project
Replace with your actual API response to generate classes for your endpoints

Real-World Pattern

Kotlin data classes with kotlinx.serialization are the standard way to deserialize JSON in Android and Kotlin Multiplatform projects. The generated code works directly with Json.decodeFromString<T>(string). Use nullable types with null defaults for fields that may not always be present in the response.