Kotlin Data Types (original) (raw)

Last Updated : 04 May, 2025

The most fundamental data type in Kotlin is the Primitive data type and all others are reference types like array and string. Java needs to use wrappers (java.lang.Integer) for primitive data types to behave like objects but Kotlin already has all data types as objects.

**There are different data types in Kotlin:

Table of Content

• Integer
• Floating-Point
• Boolean
• Character
• String
• Array

**Integer

These data types contain integer values.

Let's write a program to represent all the integer data types and their min and max values.

**Example:

Kotlin `

// Kotlin code fun main(args : Array) { var myint = 35

// add suffix L for long integer 
var mylong = 23L 

println("My integer ${myint}") 
println("My long integer ${mylong}") 

var b1: Byte = Byte.MIN_VALUE 
var b2: Byte = Byte.MAX_VALUE 
println("Smallest byte value: " +b1) 
println("Largest byte value: " +b2) 

var S1: Short = Short.MIN_VALUE 
var S2: Short = Short.MAX_VALUE 
println("Smallest short value: " +S1) 
println("Largest short value: " +S2) 

var I1: Int = Int.MIN_VALUE 
var I2: Int = Int.MAX_VALUE 
println("Smallest integer value: " +I1) 
println("Largest integer value: " +I2) 

var L1: Long = Long.MIN_VALUE 
var L2: Long = Long.MAX_VALUE 
println("Smallest long integer value: " +L1) 
println("Largest long integer value: " +L2) 

}

`

**Output:

My integer 35
My long integer 23
Smallest byte value: -128
Largest byte value: 127
Smallest short value: -32768
Largest short value: 32767
Smallest integer value: -2147483648
Largest integer value: 2147483647
Smallest long integer value: -9223372036854775808
Largest long integer value: 9223372036854775807

**Floating-Point

These data types are used to store decimal values or fractional parts.

Let's write a program to represent both the floating-point data type and its min and max value.

**Example:

Kotlin `

// Kotlin code fun main(args : Array) { // add suffix F for float var myfloat = 54F
println("My float value ${myfloat}")

var F1: Float = Float.MIN_VALUE 
var F2: Float = Float.MAX_VALUE 
println("Smallest Float value: " +F1) 
println("Largest Float value: " + F2) 

var D1: Double = Double.MIN_VALUE 
var D2: Double = Double.MAX_VALUE 
println("Smallest Double value: " + D1) 
println("Largest Double value: " + D2) 

}

`

**Output:

​My float value 54.0
Smallest Float value: 1.4E-45
Largest Float value: 3.4028235E38
Smallest Double value: 4.9E-324
Largest Double value: 1.7976931348623157E308

**Boolean

Boolean data type represents only one bit of information, either True or False. The Boolean type in Kotlin is the same as in Java. These operations, disjunction (||) or conjunction (&&), can be performed on boolean types.

Let's write a program to represent the Boolean data types.

**Example:

Kotlin `

// Kotlin code fun main(args : Array){ if (true is Boolean){ print("Yes,true is a boolean value") } }

`

**Output:

Yes,true is a boolean value

**Character

Character data type represents the small letters(a-z), Capital letters(A-Z), digits(0-9), and other symbols.

Let's write a program to represent character data type.

**Example:

Kotlin `

// Kotlin code fun main(args : Array){ var alphabet: Char = 'C' println("C is a character : ${alphabet is Char}") }

`

**Output:

C is a character : true

String

String Data type represents sequence of characters. for example : "GFG".

**Example:

Kotlin `

// Kotlin code fun main(args : Array){ var name: String = "geeksforgeeks" println("I love $name") }

`

**Output:

I love geeksforgeeks

Array

Array is a collection of elements of same type or its sub-type, which stores in a contiguous memory locations.

**Example:

Kotlin `

fun main(args: Array) { val Array = arrayOf("I", "Love", "GFG") for (i in Array) { println(i) } }

`

**Output:

I
Love
GFG

To know more about Array refer this article: Kotlin Array