Sblam!
Open-source implementation of server-side spam filtering of blog comments and forum posts. It's available as a free web service. It's open source, so you can set up your own server if you prefer. It's...
View ArticleMollom
Mollom is a freemium web service to get rid of spam, unwanted content and fake users on your Drupal, Wordpress and Joomla site or blog.
View ArticlereCAPTCHA
reCAPTCHA is a free CAPTCHA service that helps to digitize books, newspapers and old time radio shows. About 200 million CAPTCHAs are solved by humans around the world every day. In each case, roughly...
View ArticleConfident Captcha
Confident Technologies provides free CAPTCHA security software called Confident CAPTCHA, a picture CAPTCHA that stops spam and bots. Download our free CAPTCHA security software today.
View ArticlePlayThru
The PlayThru is the next generation of online human verification. It is designed to be more simple, more intuitive, and more fun than the current CAPTCHA options. We use game mechanics to create an...
View ArticleSecurimage
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...
View ArticlevisualCaptcha
visualCaptcha is a configurable captcha solution, focusing on accessibility & simplicity, whilst maintaining security. It's also localizable and free, open-source, and we encourage customizations...
View ArticleNegative Captcha
A negative captcha has the exact same purpose as your run-of-the-mill image captcha: To keep bots from submitting forms. Image ("positive") captchas do this by implementing a step which only humans can...
View ArticleFunCaptcha
FunCaptcha is a managed CAPTCHA service. It stops automated abuse and keeps human conversion high with fun visual activities that are easy to understand.
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