JSON to Kotlin data class converter tool icon
Data & JSON tools

JSON to Kotlin data class converter

Infer Kotlin data class fields from sample JSON and generate type-safe models with List, nullable types and optional kotlinx.serialization annotations, ideal for Android and Kotlin backend API modeling.

JSON input
Notes: mixed types or arrays degrade to Any?; missing or null fields become nullable types. All processing runs locally in your browser.
Kotlin output

How to Use

1. Input JSON: Paste your JSON data into the input box on the left. 2. Configure: Set the Root Class Name and choose annotation style (kotlinx.serialization or none). 3. Auto-Generate: The tool parses the JSON, infers types (String, Int, List, etc.), and generates Kotlin data class code instantly. 4. Copy Code: Click 'Copy Kotlin code' to use the generated models in your Android or backend project.

Tips & Features

Local Processing: All generation logic runs locally in your browser. Your JSON data is never uploaded to any server.

Type Inference: Supports nullable types. Mixed-type arrays degrade to Any. Field names are automatically converted to CamelCase.

Annotation Support: Select 'kotlinx.serialization' to automatically add @SerialName annotations, ensuring correct mapping between JSON fields and Kotlin properties.

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