BotDetect 3 .NET w/ audio CAPTCHA is a website security component designed to protect your registration, comment, poll, guestbook, content submission, and other online forms from automated spam submissions. BotDetect generates images with textual Captcha code rendered in them that are easily decipherable to humans -- but not to spam bots. Provides Audio Captcha alternative with secure but understandable Captcha code sound.
In essence, it allows you to focus on your code or content -- instead of on deleting spam.

'Developer Edition' includes FULL SOURCE CODE and ROYALTY FREE distribution rights!

Key features:

- Time unlimited and fully functional free version;
- 60 secure & readable Captcha image styles;
- 10 secure & accessible audio Captcha sound styles;
- Fully compatible with .NET MVC, Razor Views and .NET Ajax;
- Fully compatible with .NET Ajax and jQuery Ajax validation;
- Offers Ajax alternative written in pure Javascript without jQuery or .NET Ajax dependency;
- Fully compatible with SharePoint Server / Foundation (SP2007, SP2010, MOSS);
- Fully compatible with DotNetNuke (DNN);
- Localized Captcha generation, using various Unicode character sets and multi-language sound pronunciations;
- Custom Captcha image size, format, color scheme;
- Custom Captcha code length, style, character set, timeouts, generated code filtering;
- Many other randomization and customization options;
- Produces XHTML 1.1 Strict and WCAG AAA compliant markup;
- ADA Section 508 compliant assure accessibility;
- Visual Studio .NET 2012, 2010, 2008, 2005 and 2003 Designer support;
- Medium trust environment support for shared servers;
- Not dependent on other software so it does not bring in any additional dependencies;
- Support for IE, Firefox, Chrome, Safari and Opera browsers (desktop and mobile editions) released since 2001;
- Includes high-quality samples;
- Free 24x7 support;