Arrays and Lists in Kotlin

Arrays and lists are fundamental data structures in Kotlin, allowing you to store and manipulate collections of items. In this guide, we'll explore how to work with arrays and lists in Kotlin.


An array is a fixed-size collection of elements of the same type. You can declare and initialize arrays in Kotlin as follows:

val numbers = arrayOf(1, 2, 3, 4, 5)
val fruits = arrayOf("Apple", "Banana", "Cherry")

You can access array elements using square brackets and the index:

val firstNumber = numbers[0]
val favoriteFruit = fruits[1]


A list is a dynamic collection that can grow or shrink in size. Kotlin provides a List interface and a mutable MutableList. Here's an example:

val colors = listOf("Red", "Green", "Blue")
val mutableFruits = mutableListOf("Apple", "Banana", "Cherry")

Lists provide various methods for adding, removing, and manipulating elements:


Iterating through Arrays and Lists

You can iterate through arrays and lists using loops or functional constructs like forEach:

for (fruit in fruits) {
numbers.forEach { number ->


Arrays and lists are essential for organizing and manipulating collections of data in Kotlin. Understanding how to create, access, and manipulate these data structures is crucial for building versatile applications. Whether you're working with a fixed-size array or a dynamic list, Kotlin provides the tools you need to manage your data efficiently.

Happy coding!