JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://ajax.aspnetcdn.com/ajax/jquery.validate/1.14.0/jquery.validate.js"></script>
<div id="num_invalids"></div>
<form id="myform">
    <input type="text" name="foo" />
    <br />
    <input type="text" name="bar" />
    <br />
    <br />
    <input type="submit" />
</form>

JavaScript

$(document).ready(function() {

    $('#myform').validate({
        rules: {
            foo: {
                required: true
            },
            bar: {
                required: true
            }
        },
        invalidHandler: function(event, validator) {
            var errors = validator.numberOfInvalids(); // <- NUMBER OF INVALIDS
            $("#num_invalids").html(errors);
        }
    });

});