HTML tutorial
CSS3 tutorial
Bootstrap tutorial
JavaScript tutorial
JQuery tutorial
AngularJS tutorial
React tutorial
NodeJS tutorial
PHP tutorial
Python tutorial
Python3 tutorial
Django tutorial
Linux tutorial
Docker tutorial
Ruby tutorial
Java tutorial
C tutorial
C ++ tutorial
Perl tutorial
JSP tutorial
Lua tutorial
Scala tutorial
Go tutorial
ASP.NET tutorial
C # tutorial
Assign values to variables and add them together
Arithmetic operators are used to perform arithmetic on numbers:
| Operator | Description |
|---|---|
| + | Addition |
| - | Subtraction |
| * | Multiplication |
| ** | Exponentiation (ES2016) |
| / | Division |
| % | Modulus (Division Remainder) |
| ++ | Increment |
| -- | Decrement |
Arithmetic operators are fully described in the JS Arithmetic chapter.
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 addition assignment operator (+=) adds a value to a variable.
let x = 10;
x += 5;
Assignment operators are fully described in the JS Assignment chapter.
The + operator can also be used to add (concatenate) strings.
let text1 = "John";
let text2 = "Doe";
let text3 = text1 + " " + text2;
The result of text3 will be:
John DoeThe += assignment operator can also be used to add (concatenate) strings:
let text1 = "What a very ";
text1 += "nice day";
The result of text1 will be:
What a very nice dayWhen 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:
let x = 5 + 5;
let y = "5" + 5;
let 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!
| 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.
| Operator | Description |
|---|---|
| && | logical and |
| || | logical or |
| ! | logical not |
Logical operators are fully described in the JS Comparisons chapter.
| 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.
Bit operators work on 32 bits numbers.
| 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 |
| << | left shift | 5 << 1 | 0101 << 1 | 1010 | 10 |
| >> | right shift | 5 >> 1 | 0101 >> 1 | 0010 | 2 |
| >>> | unsigned 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.