Unobtrusive, flexible and complete spam protection for Rails applications using honeypot strategy for better user experience.

A library to make creating negative captchas less painful

A very simple rack captcha middleware via captchator.com API

Captcha-Plugin for Rails

A plugin to make the process of creating a negative captcha in Rails much less painful

A simple way to add honeypot captchas to Rails forms

Captcha Gem for Rails, which generates captcha image by Rust.

Captcha library which uses imagemagick to create captchas

TwoCaptcha allows you to solve captchas with manual labor

Ruby package for easy integration with the API of 2captcha captcha solving service to bypass recaptcha, hcaptcha, funcaptcha, geetest and solve any other captchas.

A Rails captcha gem that attempts to determine whether or not a user is human.

ZeroCaptcha allows companies to solve captchas with artificial intelligence software, which is faster than humans and very accurate

Submit captcha images and retrieve the text as a string.

Wrapper for Captchabot.com

Captchator as Rack middleware, and helpers for sinatra.

Due to many unrequited complaints to the recaptcha team with regard to its unreadability for real human users, this gem offers a more readable selection of captcha images.

NO LONGER MAINTAINED AND NOT RECOMMENDED, AS BOTS ARE ABLE TO RESOLVE CAPTCHAS BETTER THAN HUMANS. Based on Login Attempts check if captcha is necessary. It stores a permanent cookie and uses a table for tracking login requests.

Captcha based on encyrpting and decrypting user data by mathematical operation

A simple way to add zero friction captchas to Rails forms

wxianfeng_simple_captcha is captcha for rails,modified from simple_captcha .