JSFiddle - React, Tailwind, and code Playground
HTML
<input type="checkbox" value="a">
<input type="checkbox" value="b">
<input type="checkbox" value="c">
JavaScript
jQuery(document).ready(function(){
jQuery('input:checkbox').change(
function(){
alert("d");
if (jQuery('input:checkbox:checked').length == jQuery('input:checkbox').length){
alert('Alert Text.');
}
});
});