reCAPTCHA 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... Free Web No features added Add a feature 123 Like
visualCaptcha A configurable captcha solution, focusing on accessibility & simplicity whilst maintaining security. Free Open Source Self-Hosted GitHub Mobile friendly Add a feature 2 Like Discontinued As from Dec 26, 2016: Please note visualCaptcha is no longer actively developed. It still works and should continue to, but it won't be improved by the initial team anymore. ... Source: https://github.com/emotionLoop/visualCaptcha/blob/master/README.md
UniqPin UniqPin is a free for non-commercial use service which destiny improve ability of interfaces detect a human or a computer operate with it. Surpassing a CAPTCHA... Free Personal Self-Hosted JavaScript PHP No features added Add a feature 3 Like
Mollom 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. Freemium Web Content analysis Add a feature 2 Like
Solve Media's CAPTCHA TYPE-IN™ Solve Media's CAPTCHA TYPE-IN ads are an easy plug-in solution that saves your users time while making your site more secure and more profitable. Instead of... Commercial Web No features added Add a feature 1 Like
Securimage 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... Free Open Source Web No features added Add a feature 2 Like
PlayThru 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... Free Web No features added Add a feature 1 Like
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... Free Open Source Linux Web No features added Add a feature 2 Like
FunCaptcha FunCaptcha is another Captcha software, but it has something more to it. No more "Write this into the box" captchas! These are Fun captchas!. Free Web No features added Add a feature 0 Like
Negative Captcha A plugin to make the process of creating a negative captcha in Rails much less painful. Free Open Source Self-Hosted No features added Add a feature 0 Like
