Learn Kotlin-playground - 10 Code Examples & CST Typing Practice Test

Kotlin Playground is an online, browser-based IDE for writing, running, and sharing Kotlin code snippets, allowing developers and learners to experiment with Kotlin without installing any tools locally.

View all 10 Kotlin-playground code examples →

Hello World in Kotlin Playground Simple Addition in Kotlin Playground Kotlin Playground If-Else Example Kotlin Playground For Loop Example Kotlin Playground While Loop Example Kotlin Playground Function Example Kotlin Playground Array Example Kotlin Playground List Example Kotlin Playground When Expression Example Kotlin Playground Nullable Example

Learn KOTLIN-PLAYGROUND with Real Code Examples

Updated Nov 26, 2025

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Code Sample Descriptions

Hello World in Kotlin Playground

fun main() {
    println("Hello World")
}

A simple Hello World example in Kotlin Playground.

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Simple Addition in Kotlin Playground

fun main() {
    val a = 5
    val b = 10
    println("Sum: ${a + b}")
}

Adds two numbers and prints the result.

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Kotlin Playground If-Else Example

fun main() {
    val num = -3
    if(num >= 0) {
        println("Positive")
    } else {
        println("Negative")
    }
}

A simple if-else example to check if a number is positive or negative.

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Kotlin Playground For Loop Example

fun main() {
    for(i in 1..5) {
        println(i)
    }
}

Prints numbers from 1 to 5 using a for loop.

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Kotlin Playground While Loop Example

fun main() {
    var i = 1
    while(i <= 5) {
        println(i)
        i++
    }
}

Prints numbers from 1 to 5 using a while loop.

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Kotlin Playground Function Example

fun greet(name: String) {
    println("Hello, $name")
}

fun main() {
    greet("Alice")
}

Defines a function to greet a user by name.

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Kotlin Playground Array Example

fun main() {
    val numbers = arrayOf(1, 2, 3, 4, 5)
    for(num in numbers) {
        println(num)
    }
}

Iterates over an array of integers and prints them.

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Kotlin Playground List Example

fun main() {
    val fruits = listOf("Apple", "Banana", "Cherry")
    for(fruit in fruits) {
        println(fruit)
    }
}

Uses a list of strings and prints each element.

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Kotlin Playground When Expression Example

fun main() {
    val num = 2
    when(num) {
        1 -> println("One")
        2 -> println("Two")
        else -> println("Other")
    }
}

Uses a when expression to print messages based on a number.

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Kotlin Playground Nullable Example

fun main() {
    val name: String? = null
    println(name?.length ?: "Name is null")
}

Demonstrates nullable types and safe calls.

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Frequently Asked Questions about Kotlin-playground

What is Kotlin-playground?

What are the primary use cases for Kotlin-playground?

Learning and teaching Kotlin programming. Rapid prototyping of Kotlin scripts. Testing Kotlin language features. Sharing code examples in tutorials or forums. Experimenting with Kotlin standard and experimental libraries

What are the strengths of Kotlin-playground?

No installation required; works in any modern browser. Instant feedback and execution. Great for learning and experimentation. Shareable code snippets for collaboration. Supports Kotlin scripting and standard programming

What are the limitations of Kotlin-playground?

Not suitable for large projects or full applications. Limited file and project management. No persistent local storage beyond snippet sharing. Collaboration is limited to sharing links. Dependent on browser for execution performance

How can I practice Kotlin-playground typing speed?

CodeSpeedTest offers 10+ real Kotlin-playground code examples for typing practice. You can measure your WPM, track accuracy, and improve your coding speed with guided exercises.

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Code Sample Descriptions

Hello World in Kotlin Playground

fun main() {
    println("Hello World")
}

A simple Hello World example in Kotlin Playground.

Let’s Try →

Simple Addition in Kotlin Playground

fun main() {
    val a = 5
    val b = 10
    println("Sum: ${a + b}")
}

Adds two numbers and prints the result.

Let’s Try →

Kotlin Playground If-Else Example

fun main() {
    val num = -3
    if(num >= 0) {
        println("Positive")
    } else {
        println("Negative")
    }
}

A simple if-else example to check if a number is positive or negative.

Let’s Try →

Kotlin Playground For Loop Example

fun main() {
    for(i in 1..5) {
        println(i)
    }
}

Prints numbers from 1 to 5 using a for loop.

Let’s Try →

Kotlin Playground While Loop Example

fun main() {
    var i = 1
    while(i <= 5) {
        println(i)
        i++
    }
}

Prints numbers from 1 to 5 using a while loop.

Let’s Try →

Kotlin Playground Function Example

fun greet(name: String) {
    println("Hello, $name")
}

fun main() {
    greet("Alice")
}

Defines a function to greet a user by name.

Let’s Try →

Kotlin Playground Array Example

fun main() {
    val numbers = arrayOf(1, 2, 3, 4, 5)
    for(num in numbers) {
        println(num)
    }
}

Iterates over an array of integers and prints them.

Let’s Try →

Kotlin Playground List Example

fun main() {
    val fruits = listOf("Apple", "Banana", "Cherry")
    for(fruit in fruits) {
        println(fruit)
    }
}

Uses a list of strings and prints each element.

Let’s Try →

Kotlin Playground When Expression Example

fun main() {
    val num = 2
    when(num) {
        1 -> println("One")
        2 -> println("Two")
        else -> println("Other")
    }
}

Uses a when expression to print messages based on a number.

Let’s Try →

Kotlin Playground Nullable Example

fun main() {
    val name: String? = null
    println(name?.length ?: "Name is null")
}

Demonstrates nullable types and safe calls.

Let’s Try →

Frequently Asked Questions about Kotlin-playground

What is Kotlin-playground?

What are the primary use cases for Kotlin-playground?

What are the strengths of Kotlin-playground?

What are the limitations of Kotlin-playground?

How can I practice Kotlin-playground typing speed?

CodeSpeedTest offers 10+ real Kotlin-playground code examples for typing practice. You can measure your WPM, track accuracy, and improve your coding speed with guided exercises.