Kotlin is a statically typed programming language that makes developers happier. Concise syntax, null safety, full Java interoperability, and first-class multiplatform support.
Designed for productivity, safety, and seamless interoperability across platforms.
Eliminate NullPointerExceptions at compile time. The type system distinguishes nullable and non-nullable types.
Less boilerplate. Data classes, type inference, extension functions, and smart casts keep your code short and readable.
Share business logic across Android, iOS, web, desktop, and server with Kotlin Multiplatform.
Call Java from Kotlin and Kotlin from Java without friction. Use the entire Java ecosystem.
Lightweight concurrency with structured asynchronous programming. Write sequential-looking async code.
First-class support in IntelliJ IDEA and Android Studio. Excellent Gradle integration and compiler plugins.
A taste of modern, expressive code.
// Data class with automatic equals, hashCode, toString data class Person(val name: String, val age: Int) fun main() { val people = listOf( Person("Ada", 36), Person("Grace", 45), Person("Alan", 41) ) people .filter { it.age > 40 } .sortedBy { it.name } .forEach { println("${it.name} is ${it.age}") } }
Step-by-step lessons covering every core concept — like learnpython.org for Kotlin.
Your first Kotlin program, project structure, and core concepts in under 15 minutes.
Install the compiler, set up IntelliJ IDEA or Android Studio, and configure your toolchain.
Language features, idioms, collections, coroutines, and practical examples you can run today.