JavaScript Arithmetic Operators
Arithmetic operators perform arithmetic on numbers (literals or variables).
| Operator | Description |
|---|---|
| + | Addition |
| - | Subtraction |
| * | Multiplication |
| ** | Exponentiation ( ES2016 ) |
| / | Division |
| % | Modulus (Remainder) |
| ++ | Increment |
| -- | Decrement |
Arithmetic Operations
A typical arithmetic operation operates on two numbers.
Example
let x = 100 + 50;The two numbers can be literals
or variables:
Example
let x = a + b;or expressions:
Example
let x = (100 + 50) * a;Operators and Operands
The numbers (in an arithmetic operation) are called operands .
The operation (to be performed between the two operands) is defined by an operator .
| Operand | Operator | Operand |
|---|---|---|
| 100 | + | 50 |
Adding
The addition operator ( + ) adds numbers:
Example
let x = 5;
let y = 2;
let z = x + y;Subtracting
The subtraction operator ( - ) subtracts numbers.
Example
let x = 5;
let y = 2;
let z = x - y;Multiplying
The multiplication operator ( * ) multiplies numbers.
Example
let x = 5;
let y = 2;
let z = x * y;Dividing
The division operator ( / ) divides numbers.
Example
let x = 5;
let y = 2;
let z = x / y;Remainder
The modulus operator ( % ) returns the division remainder.
Example
let x = 5;
let y = 2;
let z = x % y;In arithmetic, the division of two integers produces a quotient and a remainder .
In mathematics, the result of a modulo operation is the remainder of an arithmetic division.
Incrementing
The increment operator ( ++ ) increments numbers.
Example
let x = 5;
x++;
let z = x;Decrementing
The decrement operator ( -- ) decrements numbers.
Example
let x = 5;
x--;
let z = x;Exponentiation
The exponentiation operator ( ** ) raises the first operand to the power of the second operand.
Example
let x = 5;
let z = x ** 2;x ** y produces the same result as Math.pow(x,y) :
Example
let x = 5;
let z = Math.pow(x,2);Operator Precedence
Operator precedence describes the order in which operations are performed in an arithmetic expression.
Example
let x = 100 + 50 * 3;Is the result of example above the same as 150 * 3, or is it the same as 100 + 150?
Is the addition or the multiplication done first?
As in traditional school mathematics, the multiplication is done first.
Multiplication ( * ) and division ( / ) have higher precedence than addition ( + ) and subtraction ( - ).
And (as in school mathematics) the precedence can be changed by using parentheses.
When using parentheses, the operations inside the parentheses are computed first:
Example
let x = (100 + 50) * 3;When many operations have the same precedence (like addition and subtraction or multiplication and division), they are computed from left to right:
Examples
let x = 100 + 50 - 3;For a full list of operator precedence values go to:
JavaScript Operator Precedence Values .