How to use the ! Operator to negate a Boolean Value in JavaScript ?

In JavaScript, you can use the ! (logical NOT) operator to negate a boolean value. The ! operator flips the truthiness of a value. If the operand is true, it becomes false, and if the operand is false, it becomes true.

Example: Here, !isTrue evaluates to false, and !isFalse evaluates to true.

Javascript

let isTrue = true;
let isFalse = false;

let negatedTrue = !isTrue;
let negatedFalse = !isFalse;

console.log(negatedTrue);  // Outputs false
console.log(negatedFalse); // Outputs true

Output

false
true