JSON to Kotlin Converter

Generate Kotlin data classes from JSON. Paste your JSON:

JSON Input

Kotlin Output

Class:

data classSerializableMoshiNullable

Generate Kotlin Data Classes

This tool converts JSON to Kotlin data classes with support for popular serialization libraries: kotlinx.serialization, Moshi, and Gson.

Example Output

@Serializable
data class User(
    val id: Int,
    @SerialName("user_name") val userName: String,
    val email: String,
    @SerialName("is_active") val isActive: Boolean
)

Serialization Options

Library	Annotation	Best For
kotlinx.serialization	`@Serializable`	Kotlin Multiplatform, modern projects
Moshi	`@Json`	Android, Square ecosystem
Gson	`@SerializedName`	Legacy Android projects

Type Mapping

JSON	Kotlin
string	`String`
integer	`Int` / `Long`
decimal	`Double`
boolean	`Boolean`
null	`String?`
array	`List<T>`
object	Nested data class

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