This script will prevent Marketo form submission if a user enters a non-business email (Gmail, Hotmail, etc.)

preventNonBusinessEmailSubmission.js

//This script prevents Marketo form submission if a user enters non-business email (Gmail, Hotmail, Yahoo, etc.)
//It will work on any page with a Marketo form, and runs when the form is ready 
//For further info, please see Marketo form documentation, http://developers.marketo.com/documentation/websites/forms-2-0/
//Prepared by Ian Taylor and Murtza Manzur on 9/9/2014

<script>
(function (){
  // Please include the email domains you would like to block in this list
  var invalidDomains = ["@gmail.","@yahoo.","@hotmail.","@live.","@aol.","@outlook."];

  MktoForms2.whenReady(function (form){
    form.onValidate(function(){
      var email = form.vals().Email;
      if(email){
        if(!isEmailGood(email)) {
          form.submitable(false);
          var emailElem = form.getFormElem().find("#Email");
          form.showErrorMessage("Must be Business email.", emailElem);
        }else{
          form.submitable(true);
        }
      }
    });
  });
  
  function isEmailGood(email) {
    for(var i=0; i < invalidDomains.length; i++) {
      var domain = invalidDomains[i];
      if (email.indexOf(domain) != -1) {
        return false;
      }
    }
    return true;
  }

})();
</script>

I know this is old but I came across it on the Marketo developers site.

Thought you might appreciate the heads-up that you've written "submitable" instead of "submittable" here form.submitable(false); (lines 16 and 20).

Thanks for the snippet!

Thank you kind sage! I was tearing my hair out trying to figure out what was wrong with a codebase I recently inherited. It looks like they copy-pasted the same mistake and never validated functionality. Kudos to you!