Convert JSON to Kotlin Data Classes

Generate Kotlin @Serializable data classes from JSON payloads with automatic type mapping.

JSON to Kotlin Data Class Converter

Transform JSON payloads into Kotlin data classes with kotlinx.serialization annotations.

JSON Input

Root Kotlin Class Name

Generated Kotlin Data Classes

import kotlinx.serialization.Serializable
import kotlinx.serialization.SerialName

@Serializable
data class UserResponse(
    @SerialName("id")
    val id: Int,
    @SerialName("full_name")
    val full_name: String,
    @SerialName("email")
    val email: String,
    @SerialName("is_admin")
    val is_admin: Boolean,
    @SerialName("score")
    val score: Double,
    @SerialName("skills")
    val skills: List<String>,
    @SerialName("profile")
    val profile: Profile,
)

@Serializable
data class Profile(
    @SerialName("avatar_url")
    val avatar_url: String,
    @SerialName("location")
    val location: String,
)

About This Tool

JSON to Kotlin Converter transforms raw JSON into idiomatic Kotlin data classes annotated with kotlinx.serialization @Serializable and @SerialName, ready for Android and backend Kotlin development.

Key Features

Generates @Serializable Kotlin data classes

Maps Int, Double, String, Boolean, and List<T> types

Handles nested objects by extracting child data classes

How to Use This Tool

Paste your JSON payload into the input editor.
Specify your root Kotlin class name.
Copy the generated Kotlin data class hierarchy.

Why Use This Tool

Eliminates manual boilerplate when integrating REST APIs into Android (Jetpack Compose) or Ktor applications.
Generates clean, nested data class hierarchies automatically.

Pro Tips

Ensure kotlinx.serialization plugin is enabled in your build.gradle.kts to use these classes

Frequently Asked Questions

Which serialization library is supported?

Classes are generated using official kotlinx.serialization annotations (@Serializable and @SerialName), compatible with Ktor, Retrofit, and Kotlin Multiplatform.

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