Hidden field as a (re)CAPTCHA alternative in a ASP.NET MVC2 application

Question

I am writing a "contact us" form on a web project that I am currently involved with. While I've used reCAPTCHA in the past, for this project, I would prefer not to clutter the interface with extra images, fields, etc.

How many of you have had experience in adding a hidden field named something like "first_name" to your form. The idea being that if the field was not populated then the submitter would more than likely be human. But then I ask, wouldn't a bot check if the field was or was not hidden?

Answer 1

It's entirely feasible. Bots aren't very smart, and they can easily be tricked into filling these fields, some times called "honeypots".

Read:

• Stopping spambots with hashes and honeypots
• Negative CAPTCHA

Answer 2

Instead of making it a hidden field, couldn't you just hide it with CSS?