What is toUpperCase() Method in JavaScript ?

JavaScript String toUpperCase() method converts the entire string to Upper case. This method does not affect any of the special characters, digits, and the alphabets that are already in the upper case. 

Syntax:

str.toUpperCase()

Example: Here, the toUpperCase() method is called on the str string, converting all lowercase letters to uppercase. The resulting string, "HELLO WORLD", is assigned to the variable upperStr.

Javascript

const str = "hello world";
const upperStr = str.toUpperCase();

console.log(upperStr); // Output: "HELLO WORLD"

Output

HELLO WORLD