How to Use Arithmetic Operators in Kotlin: Simple Guide

In Kotlin, you use +, -, *, /, and % as arithmetic operators to perform addition, subtraction, multiplication, division, and remainder operations. These operators work with numbers like Int and Double to calculate values directly in expressions.

Syntax

Kotlin uses simple symbols for arithmetic operations:

• + for addition
• - for subtraction
• * for multiplication
• / for division
• % for remainder (modulus)

You write expressions like val result = a + b where a and b are numbers.

kotlin

val a = 10
val b = 3
val sum = a + b
val difference = a - b
val product = a * b
val quotient = a / b
val remainder = a % b

Example

This example shows how to use all basic arithmetic operators in Kotlin and prints the results.

kotlin

fun main() {
    val a = 15
    val b = 4

    println("Addition: " + (a + b))
    println("Subtraction: " + (a - b))
    println("Multiplication: " + (a * b))
    println("Division: " + (a / b))
    println("Remainder: " + (a % b))
}

Output

Addition: 19
Subtraction: 11
Multiplication: 60
Division: 3
Remainder: 3

Common Pitfalls

One common mistake is dividing two integers and expecting a decimal result. In Kotlin, dividing two Int values returns an Int by dropping the decimal part.

To get a decimal result, convert one or both numbers to Double before dividing.

kotlin

fun main() {
    val x = 7
    val y = 2

    // Wrong: integer division
    println("Integer division: " + (x / y))

    // Right: convert to Double for decimal division
    println("Decimal division: " + (x.toDouble() / y))
}

Output

Integer division: 3
Decimal division: 3.5

Quick Reference

Operator	Meaning	Example
+	Addition	5 + 3 = 8
-	Subtraction	5 - 3 = 2
*	Multiplication	5 * 3 = 15
/	Division	5 / 3 = 1 (Int division)
%	Remainder	5 % 3 = 2

Key Takeaways

Use +, -, *, /, and % for basic arithmetic in Kotlin.

Integer division drops decimals; convert to Double for decimal results.

Arithmetic operators work with numeric types like Int and Double.

Remember % gives the remainder after division.

Always check types to avoid unexpected results in calculations.