JSFiddle - React, Tailwind, and code Playground

HTML

<input required="required" name="hello_world" type="text">
<input required="1" name="foo" type="text">
<input required="true" name="bar" type="text">
<input required name="baz" type="text">
    
    <button>go</button>

JavaScript

$('button').on('click',function(){
    $('body').append($(':required').length);
});