The modern default for Android development

Kotlin Compiler Online — Run Kotlin Code in Your Browser

Kotlin runs on the JVM, interoperates directly with Java, and is now Google's preferred language for Android development. It trims a lot of Java's boilerplate — null safety, data classes, and concise syntax baked in.

fun main() {
    println("Hello, world!")
}

What people use Kotlin here for

• Practicing Kotlin syntax before an Android project
• Testing null-safety behavior or a data class in isolation
• Trying Kotlin without opening Android Studio

No installs, no signup

Code you write here runs on a real, self-hosted Judge0 execution backend — actual Kotlin compiler or interpreter output, not a simulation. Your code compiles through the real Kotlin compiler and runs on the JVM — the same toolchain Android Studio uses under the hood, without opening it. See the full list of supported languages or read more about how AnyCompiler works.