Assignment Operators
JavaScript Assignment Operators
Assignment operators assign values to JavaScript variables.
Given that x = 10 and y = 5, the table below explains the assignment operators:
| Oper | Example | Same As | Result | |
|---|---|---|---|---|
| = | x = y | x = y | x = 5 | Try it » |
| += | x += y | x = x + y | x = 15 | Try it » |
| -= | x -= y | x = x - y | x = 5 | Try it » |
| *= | x *= y | x = x * y | x = 50 | Try it » |
| /= | x /= y | x = x / y | x = 2 | Try it » |
| %= | x %= y | x = x % y | x = 0 | Try it » |
| : | x: 45 | size.x = 45 | x = 45 | Try it » |
Logical Assignment Operators
| Oper | Example | Result | |
|---|---|---|---|
| &&= | true &&= 10 | x = 10 | Try it » |
| ||= | false ||= 10 | x = 10 | Try it » |
| ??= | null ??= 10 | x = 10 | Try it » |
The Conditional (Ternary) Operator
The conditional operator assigns a value to a variable based on a condition.
| Syntax | Example | |
|---|---|---|
| (condition) ? x : y | (age < 18) ? false : true | Try it » |
The Spread (...) Operator
The ... operator splits iterables into individual elements.
| Syntax | Example | |
|---|---|---|
| const myArr = [1, 2, 3]; | let xMin = Math.min(...myArr); | Try it » |
Learn More:
Study our JavaScript Assignment Tutorial.
Browser Support
Assignment is an ECMAScript1 (JavaScript 1997) feature.
It is supported in all browsers:
| Chrome | Edge | Firefox | Safari | Opera | IE |
| Yes | Yes | Yes | Yes | Yes | Yes |
The Nullish Coalescing Operator (??)
The ?? operator returns the first argument if it is not nullish
(null or undefined).
Otherwise it returns the second argument.
Browser Support
?? is a JavaScript 2020 feature.
ES 2020 is supported in all modern browsers since September 2020:
| Chrome 85 |
Edge 85 |
Firefox 79 |
Safari 14 |
Opera 71 |
| Aug 2020 | Aug 2020 | Mar 2020 | Sep 2020 | Sep 2020 |
