Kotlin Operators

Operators are used to perform operations on variables and values

Kotlin Operators

Operators are used to perform operations on variables and values.

The value is called an operand, while the operation (to be performed between the two operands) is defined by an operator:

Operand Operator Operand
100 + 50

In the example below, the numbers 100 and 50 are operands, and the + sign is an operator:

Example

var x = 100 + 50

Although the + operator is often used to add together two values, like in the example above, it can also be used to add together a variable and a value, or a variable and a variable:

Example

var sum1 = 100 + 50       // 150 (100 + 50)
var sum2 = sum1 + 250     // 400 (150 + 250)
var sum3 = sum2 + sum2    // 800 (400 + 400)

Kotlin divides the operators into the following groups:

  • Arithmetic operators
  • Assignment operators
  • Comparison operators
  • Logical operators
  • Arithmetic Operators

    Arithmetic operators are used to perform common mathematical operations.

    Operator Name Description Example Try it
    + Addition Adds together two values x + y Try it »
    - Subtraction Subtracts one value from another x - y Try it »
    * Multiplication Multiplies two values x * y Try it »
    / Division Divides one value from another x / y Try it »
    % Modulus Returns the division remainder x % y Try it »
    ++ Increment Increases the value by 1 ++x Try it »
    -- Decrement Decreases the value by 1 --x Try it »

    Kotlin Assignment Operators

    Assignment operators are used to assign values to variables.

    In the example below, we use the assignment operator (=) to assign the value 10 to a variable called x:

    Example

    var x = 10

    The addition assignment operator (+=) adds a value to a variable:

    Example

    var x = 10
    x += 5

    A list of all assignment operators:

    Operator Example Same As Try it
    = x = 5 x = 5 Try it »
    += x += 3 x = x + 3 Try it »
    -= x -= 3 x = x - 3 Try it »
    *= x *= 3 x = x * 3 Try it »
    /= x /= 3 x = x / 3 Try it »
    %= x %= 3 x = x % 3 Try it »

    Kotlin Comparison Operators

    Comparison operators are used to compare two values, and returns a Boolean value: either true or false.

    Operator Name Example Try it
    == Equal to x == y Try it »
    != Not equal x != y Try it »
    > Greater than x > y Try it »
    < Less than x < y Try it »
    >= Greater than or equal to x >= y Try it »
    <= Less than or equal to x <= y Try it »

    You will learn much more about Booleans in the Boolean chapter and Conditions.

    Kotlin Logical Operators

    Logical operators are used to determine the logic between variables or values:

    Operator Name Description Example Try it
    &&  Logical and Returns true if both statements are true x < 5 &&  x < 10 Try it »
    ||  Logical or Returns true if one of the statements is true x < 5 || x < 4 Try it »
    ! Logical not Reverse the result, returns false if the result is true Try it »