Kotlin Data Types Last Updated : 04 May, 2025 Comments Improve Suggest changes Like Article Like Report 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 ContentIntegerFloating-PointBooleanCharacterStringArrayIntegerThese data types contain integer values.Data TypeBitsMin ValueMax Valuebyte8 bits-128127short16 bits-3276832767int32 bits-21474836482147483647long64 bits-9223372036854775808 9223372036854775807Let'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<String>) { 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 35My long integer 23Smallest byte value: -128Largest byte value: 127Smallest short value: -32768Largest short value: 32767Smallest integer value: -2147483648Largest integer value: 2147483647Smallest long integer value: -9223372036854775808Largest long integer value: 9223372036854775807Floating-PointThese data types are used to store decimal values or fractional parts.Data TypeBitsMin ValueMax Valuefloat32 bits1.40129846432481707e-453.40282346638528860e+38double64 bits4.94065645841246544e-3241.79769313486231570e+308Let'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<String>) { // 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 54.0Smallest Float value: 1.4E-45Largest Float value: 3.4028235E38Smallest Double value: 4.9E-324Largest Double value: 1.7976931348623157E308BooleanBoolean 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.Data TypeBitsData Rangeboolean1 bittrue or falseLet's write a program to represent the Boolean data types.Example: Kotlin // Kotlin code fun main(args : Array<String>){ if (true is Boolean){ print("Yes,true is a boolean value") } } Output:Yes,true is a boolean valueCharacterCharacter data type represents the small letters(a-z), Capital letters(A-Z), digits(0-9), and other symbols.Data TypeBitsMin ValueMax Valuechar16 bits'\u0000' (0)'\uFFFF' (65535)Let's write a program to represent character data type.Example: Kotlin // Kotlin code fun main(args : Array<String>){ var alphabet: Char = 'C' println("C is a character : ${alphabet is Char}") } Output:C is a character : trueStringString Data type represents sequence of characters. for example : "GFG".Example: Kotlin // Kotlin code fun main(args : Array<String>){ var name: String = "geeksforgeeks" println("I love $name") } Output:I love geeksforgeeksArrayArray 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<String>) { val Array = arrayOf("I", "Love", "GFG") for (i in Array) { println(i) } } Output:ILoveGFGTo know more about Array refer this article: Kotlin Array Comment More infoAdvertise with us Next Article Kotlin Variables P Praveenruhil Follow Improve Article Tags : Python Kotlin Kotlin Basics Practice Tags : python Similar Reads Kotlin Tutorial This Kotlin tutorial is designed for beginners as well as professional, which covers basic and advanced concepts of Kotlin programming language. In this Kotlin tutorial, you'll learn various important Kotlin topics, including data types, control flow, functions, object-oriented programming, collecti 4 min read OverviewIntroduction to KotlinKotlin is a statically typed, general-purpose programming language developed by JetBrains, which has built world-class IDEs like IntelliJ IDEA, PhpStorm, Appcode, etc. It was first introduced by JetBrains in 2011 as a new language for the JVM. Kotlin is an object-oriented language, and a better lang 4 min read Kotlin Environment setup for Command LineTo set up a Kotlin environment for the command line, you need to do the following steps:Install the Java Development Kit (JDK): Kotlin runs on the Java virtual machine, so you need to have the JDK installed. You can download the latest version from the official Oracle website.Download the Kotlin com 2 min read Kotlin Environment setup with Intellij IDEAKotlin is a statically typed, general-purpose programming language developed by JetBrains that has built world-class IDEs like IntelliJ IDEA, PhpStorm, Appcode, etc. It was first introduced by JetBrains in 2011. Kotlin is object-oriented language and a better language than Java, but still be fully i 2 min read Hello World program in KotlinHello, World! It is the first basic program in any programming language. Let's write the first program in the Kotlin programming language. The "Hello, World!" program in Kotlin: Open your favorite editor, Notepad or Notepad++, and create a file named firstapp.kt with the following code. // Kotlin He 2 min read BasicsKotlin Data TypesThe 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 3 min read Kotlin VariablesIn Kotlin, every variable should be declared before it's used. Without declaring a variable, an attempt to use the variable gives a syntax error. The declaration of the variable type also decides the kind of data you are allowed to store in the memory location. In case of local variables, the type o 2 min read Kotlin OperatorsOperators are the symbols that operate on values to perform specific mathematical or logical computations on given values. They are the foundation of any programming language. Example:Kotlinfun main(args: Array<String>) { var a= 10 + 20 println(a) }Output:30Explanation: Here, â+â is an additio 4 min read Kotlin Standard Input/OutputIn this article, we will discuss how to take input and how to display the output on the screen in Kotlin. 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Table of ContentWhat are Functions?Example of a FunctionTypes of Fu 7 min read Kotlin Default and Named argumentIn most programming languages, we need to specify all the arguments that a function accepts while calling that function, but in Kotlin, we need not specify all the arguments that a function accepts while calling that function, so it is one of the most important features. We can get rid of this const 7 min read Kotlin RecursionIn this tutorial, we will learn about Kotlin Recursive functions. Like other programming languages, we can use recursion in Kotlin. A function that calls itself is called a recursive function, and this process of repetition is called recursion. Whenever a function is called then there are two possib 3 min read Kotlin Tail RecursionIn a traditional recursion call, we perform our recursive call first, and then we take the return value of the recursive call and calculate the result. 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The existing class is known as the superclass or base class, and the new class is known as the subclass or derived class. The subclass inherits all the properties and functions of the superclass, and can 10 min read Kotlin InterfacesIn Kotlin, an interface is a collection of abstract methods and properties that define a common contract for classes that implement the interface. An interface is similar to an abstract class, but it can be implemented by multiple classes, and it cannot have state.Interfaces are custom types provide 7 min read Kotlin Data ClassesIn Kotlin, we often create classes just to hold data. These are called data classes, and they are marked with the data keyword. Kotlin automatically creates some useful functions for these classes, so you donât have to write them yourself.What Is a Data Class?A data class is a class that holds data. 3 min read Kotlin Sealed ClassesKotlin introduces a powerful concept that doesn't exist in Java: sealed classes. 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Kotlin supports 4 min read Kotlin extension functionKotlin provides a powerful feature called Extension Functions that allows us to add new functions to existing classes without modifying them or using inheritance. This makes our code more readable, reusable, and clean.What is an Extension Function?An extension function is a function that is defined 4 min read Kotlin genericsGenerics are one of Kotlin's most powerful features. They allow us to write flexible, reusable, and type-safe code. With generics, we can define classes, methods, and properties that work with different types while still maintaining compile-time type safety.What Are Generics?A generic type is a clas 6 min read Exception HandlingKotlin Exception Handling - try, catch, throw and finallyException handling is an important part of programming that helps us manage errors in our code without crashing the entire application. In this article, we will learn about exception handling in Kotlin, how to use try, catch, throw, and finally blocks, and understand different types of exceptions.Ko 5 min read Kotlin Nested try block and multiple catch blockIn Kotlin, exception handling allows developers to manage errors gracefully and prevent application crashes. In this article, we will explore two advanced exception handling concepts in Kotlin:Nested try-catch blocksMultiple catch blocks, including how to simplify them using a when expression.Nested 3 min read Null SafetyKotlin Null SafetyKotlin has a powerful type system that helps developers avoid one of the most common problems in programming: Null Pointer Exceptions. In many languages like Java, trying to use a variable that holds null can cause a NullPointerException (NPE), which can crash your application if not handled properl 7 min read Kotlin Type Checking and Smart CastingKotlin allows you to determine the type of a variable at runtime using the is operator. This feature is commonly used to handle logic based on the dynamic type of an object, enabling type-safe operations within control flow blocks.Using if-else Blocks for Type CheckingKotlinfun main() { val name = " 3 min read Kotlin Explicit Type CastingKotlin provides both smart casting and explicit type casting mechanisms to handle type conversions safely and effectively. In Smart Casting, we generally use is or !is an operator to check the type of variable, and the compiler automatically casts the variable to the target type, but in explicit typ 3 min read Like