Gem that uses RuCaptcha API to solver any type of captcha

generate captcha by dalli,use the memcache

adds audio support to simple captcha

Captcha form Jike API

Captcha Client for YunPian.com

RMagickCaptcha is a gem that implements captcha for using in Rails application.

A simple and custom captcha for Rails3.

Simple captcha based on plain text questions.

Simple Audio Extension to Simple Captcha

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

HumanDetector is a friendly logic captcha for Rails the doesn't require any external system dependency (e.g. external captcha API connections). It uses a simple question that any 7 or more years old human can understand, but that a spambot will not be able to answer. This Gem supports Ruby v1.9.2...

A simple image captcha gem

A captcha verification approach for Rails apps, directly integrated into ActiveRecord’s validation mechanism and providing helpers for ActionController and ActionView.

ReCaptcha implements view helpers to generate ReCaptcha code, with the noscript counterpart, required methods that interface with the HTTP API for captcha verification, a DSL to generate a before_filter and the code to implement AJAX captcha validation.

MVC based Math, Logic Captcha

A simple CAPTCHA implementation for Rails 5+ based on RMagick.

Simple lib to generate a math_captcha to prevent spammers in form. Supports localization.

Simple reverse captcha solution that consist in create a hidden field that should be always empty.

It's a Rails Captcha Engine for Rails 3 applications.

simple stupid captcha