WordPress Contact Form Slider provides four captcha modes, this example demonstrate the Hidden Field Captcha Mode. The robots usually fills all input fields then try to submit. With this mode, the Contact Form includes an empty hidden field and check that value. The plugin is send the Contact Form when the hidden field value is still empty. With this method, the visitor’s no need to do any extra things and the field is absolutely invisible for them.
Click on the Contact Icon on the left side or here to try out!