Hi,
Thanks for your question! We actually use what is known as a “smart captcha” for Cognito Forms. Basically, we have rules in place that allow our forms to automatically detect spam bots based on the type of actions that are taken on the form. These actions would all naturally happen if a human used the form, so the captcha doesn’t appear and won’t frustrate your users. If the actions don’t take place, which would happen if there was a spam bot running, then the captcha appears and keeps the bot from being able to submit the form.
This is an automatic function of Cognito Forms, so there isn’t any additional work needed on your end to prevent spam form entries.
Unfortunately, we do not currently have a way to delete entries in bulk. We are however working on this for a future release, and you follow the progress of this on our idea board.
I hope this answers your question. Please let me know if you have any other questions or concerns.