Smtp JS

mail.html

<!-- SmtpJs -->
   <script src="https://smtpjs.com/v3/smtp.js"></script>
   <script>
      $('.btn-submit').click(function () {

         /*var maillist = [
            '****@***.com',
            '****@***.com',
         ];*/

         Email.send({
            SecureToken: "tokencode",
            To: 'to@mail.com',
            From: 'from@mail.com',
            Subject: "Contact Form",
            Body: 'Name: ' + $('#name').val() + '<br> Phone: ' + $('#phone').val() + '<br> Message: ' + $(
               '#message').val()
         }).then(
            message => alert('Your form has been submitted successfully.')
         );

         return false;
      });
   </script>