You can add a honeypot on you form. A honeypot is a field added to the form that the users can’t see due to CSS or JavaScript (which hides the field). When a spam bot comes to a form, it fills out EVERY input field, but it ignores the CSS code. This is the behavior we can exploit. You would create a regular form input field with HTML (this will be the honeypot field). The spam bot will see the field, but you’ll use JavaScript to hide the field from users. If the honeypot field is empty, the Javascript code would submit the form. On the other hand, if the honeypot field has data, you know it could only have been filled out by a spam bot.