HTML5 form validation before reCAPTCHA's

You have to do it programmatically thanks to a new v2 grecaptcha method: grecaptcha.execute() so that recaptcha doesn't replace the button's default click event which was preventing the default HTML5 form validation.

The event path is:

  1. Submit button click event: browser built-in form validation
  2. Form submit event: call grecaptcha.execute()
  3. reCAPTCHA callback: submit the form

$('#form-contact').submit(function (event) {
    event.preventDefault();
    grecaptcha.reset();
    grecaptcha.execute();
  });

function formSubmit(response) {
  // submit the form which now includes a g-recaptcha-response input
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="https://www.google.com/recaptcha/api.js"></script>
<form action="?">
  <div class="g-recaptcha" 
       data-sitekey="your-key"
       data-size="invisible"
       data-callback="formSubmit">
  </div>
  <button type="submit">Submit</button>
</form>


Here is my solution to get HTML5 validation + Invisible recaptcha:

HTML:

<form id="my-form">
    <!-- Your form fields ... -->
    <div class="g-recaptcha"
        data-sitekey="..."
        data-callback="submitMyForm"
        data-size="invisible">
    </div>
    <button type="submit">Submit</button>
</form>

JS:

var myForm = $('my-form');

function submitMyForm () {
    myForm.trigger('submit', [true]);
}

$(function () {
    myForm.on('submit', function (e, skipRecaptcha) {
        if(skipRecaptcha) {
            return;
        }

        e.preventDefault();
        grecaptcha.execute();
    });
  })

Hi got a working solution here. Working with invisible Recaptcha.

jQuery(document).ready(function() {
    var commentform = jQuery("#commentform");
    commentform.on("click", "#submit-comment", function(e) {
      if(commentform[0].checkValidity()) {
        e.preventDefault();
        grecaptcha.execute();
      }
    });
});

function submitCommentForm(data) {
    document.getElementById("commentform").submit();
}
<form action="blaba.php" method="post" id="commentform" class="comment-form">
  <div class="form-submit">
    <div data-callback="submitCommentForm" data-sitekey="yourkey" class="g-recaptcha" data-size="invisible">
    <button id="submit-comment">Leave a comment</button>
  </div>
</form>