Logical Operators
JavaScript Logical Operators
Logical operators are used to determine the logic between variables or values.
Given that x = 6 and y = 3, the table below explains the logical operators:
| Oper | Name | Example | Try it |
|---|---|---|---|
| && | AND | (x < 10 && y > 1) is true | Try it » |
| || | OR | (x === 5 || y === 5) is false | Try it » |
| ! | NOT | !(x === y) is true | Try it » |
Browser Support
Logical Operators is an ECMAScript1 (JavaScript 1997) feature.
It is supported in all browsers:
| Chrome | Edge | Firefox | Safari | Opera | IE |
| Yes | Yes | Yes | Yes | Yes | Yes |
Conditional (Ternary) Operator
The conditional operator assigns a value to a variable based on a condition.
| Syntax | Example | Try it |
|---|---|---|
| (condition) ? x : y | (z < 18) ? x : y | Try it » |
Browser Support
The Ternary Operator 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.
The nullish operator is supported in all browsers since March 2020:
| Chrome 80 | Edge 80 | Firefox 72 | Safari 13.1 | Opera 67 |
| Feb 2020 | Feb 2020 | Jan 2020 | Mar 2020 | Mar 2020 |
The Optional Chaining Operator (?.)
The ?. operator returns undefined if an object is
undefined or null (instead of throwing an error).
Example
// Create an object:
const car = {type:"Fiat", model:"500", color:"white"};
// Ask for car name:
document.getElementById("demo").innerHTML = car?.name;
Try it Yourself »
The optional chaining operator is supported in all browsers since March 2020:
| Chrome 80 | Edge 80 | Firefox 72 | Safari 13.1 | Opera 67 |
| Feb 2020 | Feb 2020 | Jan 2020 | Mar 2020 | Mar 2020 |
