Convert
JSON to Kotlin
Generate Kotlin data classes from JSON. Nullable types inferred, ready for kotlinx.serialization or Moshi.
data class Profile(
val email: String,
val verified: Boolean
)
data class Root(
val id: Long,
val name: String,
val roles: List<String>,
val profile: Profile
)Why use our JSON to Kotlin?
100% private
Everything runs in your browser. Your data never leaves your device — safe for production payloads.
Instant results
No round trips, no rate limits, no login. Format, validate and inspect megabytes of JSON in milliseconds.
Standards-first
Follows RFC 8259 / ECMA-404 exactly. Reports errors with precise line and column diagnostics.
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OpenRelated reading
Deep-dive guides that pair well with the JSON to Kotlin.
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How APIs use JSON for data exchange
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Understanding JSON objects, arrays and nested data
The two containers JSON gives you — objects and arrays — combine into every real-world payload. Here's how to model them well.
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What is JSON? A developer's introduction
Understand the JSON data format, its history, and why it dominates modern APIs and configuration files.
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