# CAPTCHA alternatives

If your web forms are getting spammed, and <span class="caps">CAPTCHA</span> isn’t a good solution, here are some possible alternatives.

- [http://isc.sans.org/diary.html?storyid=1836](http://isc.sans.org/diary.html?storyid=1836)
- [http://softwareas.com/captcha-alternatives-and-end-user-attitudes](http://softwareas.com/captcha-alternatives-and-end-user-attitudes)
- I’ve taken to renaming our feedback pages, and then using robots.txt to prevent search engines from indexing their new names.

- Related Link: [https://kb.ucla.edu/link/438](https://kb.ucla.edu/link/438)

The Akismet service has a good reputation, and is widely used by Wordpress amongst others. It could be another layer of protection against spam.

- [http://akismet.com/](http://akismet.com/) (official site)
- [http://codex.wordpress.org/Akismet](http://codex.wordpress.org/Akismet) (an example of it in a blogcentric <span class="caps">CMS</span>)

Jared Smith of [WebAIM](http://www.webaim.org) has compiled a series of server-side processing techniques that get rid of spam without the use of   
<span class="caps">CAPTCHA</span>. Scripts are provided in <span class="caps">PHP</span>.

[Spam-Free Accessible Forms](http://webaim.org/blog/2007/03/07/spam_free_accessible_forms/)

The scripts include:

- Detect spam-like content within submitted form elements
- Detect content within a hidden form element
- Validate the submitted form values
- Search for the same content in multiple form elements
- Generate dynamic content to ensure the form is submitted within a   
    specific time window or by the same user
- Create a multi-stage form or form verification page
- Ensure the form is posted from your server