--- title: String is uppercase type: snippet language: javascript tags: [string] cover: flower-portrait-7 dateModified: 2020-09-15T16:28:04+03:00 --- Checks if a string is upper case. - Convert the given string to upper case, using `String.prototype.toUpperCase()` and compare it to the original. ```js const isUpperCase = str => str === str.toUpperCase(); ``` ```js isUpperCase('ABC'); // true isUpperCase('A3@$'); // true isUpperCase('aB4'); // false ```