ActsAsTextcaptcha provides spam protection for Rails models with text-based logic question captchas. Questions are fetched from Rob Tuley's textcaptcha.com They can be solved easily by humans but are tough for robots to crack.

Despamilator is a plugin based spam detector designed for use on your web forms borne out of two annoyances: Spam being submitted in my web forms and CAPTCHAS being intrusive. Despamilator will apply some commonly used heuristics from the world of anti-spam to help you decide whether your users are human or machine.

Arithmetic Captcha

RubyGem package for visualCaptcha's backend service

AntiCaptcha api ruby wrapper

.

Drop in feedback engine with customizable fields, and captcha available

SimpleCaptcha is available to be used with Rails 3 or above and also it provides the backward compatibility with previous versions of Rails.

Rails extension for Cloudflare's Turnstile CAPTCHA alternative. This gem should work with Rails 6.x and 7.x, and with Faraday 1.x and 2.x.

This is mt first gem

Block repetetive requests from logged_in users and shows captcha.

My version of SimpleCaptcha

A simple and fast image captcha generator that uses opencv and memcached.

Ruby wrapper for Yandex.Cleanweb

A honeypot style captcha extension for ActiveRecord. Simple one-line inclusion in the model combined with a simple form field should trap the bad guys in the molasses.

Metabypass | Ruby-based easy implementation for solving any type of captcha by Metabypass

This is a gem wrapper for tiny captcha in C with no dependencies.

create captcha for api based project

dongsx

Implements view helpers for the ASIRRA CAPTCHA system for Rails-based websites