# JavaScript Operators Posted by

# JavaScript Operators

### Example

Assign values to variables and add them together:

var x = 5;         // assign the value 5 to
x
var y = 2;         // assign the value
2 to y
var z = x + y;     // assign the value 7 to z (5 + 2)

The

assignment

operator (
``` = ```
) assigns a value to a variable.

### Assignment

var x = 10;

The

operator (
``` + ```

var x = 5;
var y = 2;
var z = x + y;

The

multiplication

operator (
``` * ```
) multiplies numbers.

var x = 5;
var y = 2;
var z = x * y;

## JavaScript Arithmetic Operators

Arithmetic operators are used to perform arithmetic on numbers:

Operator Description
Subtraction
* Multiplication
** Exponentiation (
ES2016
)
/ Division
% Modulus (Division Remainder)
++ Increment
Decrement

Arithmetic operators are fully described in the

JS Arithmetic

chapter.

## JavaScript Assignment Operators

Assignment operators assign values to JavaScript variables.

Operator Example Same As
= x = y x = y
+= x += y x = x + y
-= x -= y x = x – y
*= x *= y x = x * y
/= x /= y x = x / y
%= x %= y x = x % y
**= x **= y x = x ** y

The

operator (
``` += ```
) adds a value to a variable.

### Assignment

var x = 10;
x += 5;

Assignment operators are fully described in the

JS Assignment

chapter.

## JavaScript String Operators

The
``` + ```
operator can also be used to add (concatenate) strings.

### Example

var
txt1 = “John”;
var
txt2 = “Doe”;
var
txt3 = txt1 + ” ” + txt2;

The result of txt3 will be:

``` John Doe ```

The
``` += ```
assignment operator can also be used to add (concatenate) strings:

### Example

var
txt1 = “What a very “;
txt1 += “nice day”;

The result of txt1 will be:

``` What a very nice day ```

When used on strings, the + operator is called the concatenation operator.

Adding two numbers, will return the sum, but adding a number and a string will return a string:

### Example

var
x = 5 + 5;
var
y = “5” + 5;
var
z = “Hello” + 5;

The result of

x

,

y

, and

z

will be:

``` 10 55 Hello5 ```

If you add a number and a string, the result will be a string!

## JavaScript Comparison Operators

Operator Description
== equal to
=== equal value and equal type
!= not equal
!== not equal value or not equal type
> greater than
< less than
>= greater than or equal to
<= less than or equal to
? ternary operator

Comparison operators are fully described in the

JS Comparisons

chapter.

## JavaScript Logical Operators

Operator Description
&& logical and
|| logical or
! logical not

Logical operators are fully described in the

JS Comparisons

chapter.

## JavaScript Type Operators

Operator Description
typeof Returns the type of a variable
instanceof Returns true if an object is an instance of an object type

Type operators are fully described in the

JS Type Conversion

chapter.

## JavaScript Bitwise Operators

Bit operators work on 32 bits numbers.

Any numeric operand in the operation is converted into a 32 bit number.
The result is converted back to a JavaScript number.

Operator Description Example Same as Result Decimal
& AND 5 & 1 0101 & 0001 0001 1
| OR 5 | 1 0101 | 0001 0101 5
~ NOT ~ 5 ~0101 1010 10
^ XOR 5 ^ 1 0101 ^ 0001 0100 4
<< Zero fill left shift 5 << 1 0101 << 1 1010 10
>> Signed right shift 5 >> 1 0101 >> 1 0010 2
>>> Zero fill right shift 5 >>> 1 0101 >>> 1 0010 2

The examples above uses 4 bits unsigned examples. But JavaScript uses 32-bit signed numbers.
Because of this, in JavaScript, ~ 5 will not return 10. It will return -6.
~00000000000000000000000000000101 will return 11111111111111111111111111111010

Bitwise operators are fully described in the

JS
Bitwise

chapter.

## Exercise:

Multiply
``` 10 ```
with
``` 5 ```
```alert(10  5);