JSFiddle - React, Tailwind, and code Playground

HTML

<form name="myform" action="javascript:void(0);">
    <input type='radio' name='$response' value='5' />
      <input type='radio' name='$response' value='4' />
      <input type='radio' name='$response' value='3' />
      <input type='radio' name='$response' value='2' />
      <input type='radio' name='$response' value='1' />
    <input type="submit" />
</form>

JavaScript

var myform = document.forms['myform'];
myform.onsubmit = function() {
   var elements = myform.getElementsByTagName("input");
   var value;
   for(var i =0; i< elements.length; i++) {
      if(elements[i].type == "radio" && elements[i].checked) {
         value = elements[i].value;
         break;
      }
   }
    alert(value);
   return false;
}