Securimage is a script for generating complex images and CAPTCHA codes to protect forms from spam and abuse. It can be easily added into existing forms on your website to provide protection from spam bots. Securimage does everything from generating the CAPTCHA images to validating the typed code. Audible codes can be streamed to the browser with Flash for the vision impaired.
Confident Technologies provides free CAPTCHA security software called Confident CAPTCHA, a picture CAPTCHA that stops spam and ...
Open-source implementation of server-side spam filtering of blog comments and forum posts. It's available as a free web servic ...
A negative captcha has the exact same purpose as your run-of-the-mill image captcha: To keep bots from submitting forms. Image ...
What Does NoMoreCaptchas Do? NoMoreCaptchas stops bots that try to register and log in to websites, leave spam comments on blo ...
reCAPTCHA is a free CAPTCHA service that helps to digitize books, newspapers and old time radio shows. About 200 million CAPTC ...
UniqPin is a free for non-commercial use service which destiny improve ability of interfaces detect a human or a computer oper ...
visualCaptcha is a configurable captcha solution, focusing on accessibility & simplicity, whilst maintaining security. It' ...