JavaScript Boolean() function explained


JavaScript has a built-in Boolean() function that you can use to turn any value into its boolean equivalent.

For example, the following string value z will be converted to true using the Boolean() function:

let bool = Boolean('z');
console.log(bool); // true
console.log(typeof bool); // "boolean"

Passing a truthy value to the function will return true while passing falsy values will return false:

let boolNull = Boolean(null);
console.log(boolNull); // false
console.log(typeof boolNull); // "boolean"

See also: JavaScript truthy falsy values explained

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