Tencent Cloud Ruby SDK is the official software development kit, which allows Ruby developers to write software that makes use of Tencent Cloud service CAPTCHA.

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

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.

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

Captcha-Plugin for Rails

Arithmetic Captcha

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NO LONGER MAINTAINED AND NOT RECOMMENDED, AS BOTS ARE ABLE TO RESOLVE CAPTCHAS BETTER THAN HUMANS.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.

Antispam helps prevent spam in your Rails applications by checking against DNS blacklists and spam-prevention databases. It has two core features: (1) IP-based spam detection using Project Honey Pot to block known spammers automatically, and (2) content-based spam detection using Defendium’s machine learning API, which is free for up to 1,000 checks per day. Blacklist lookups are cached for 24 hours to minimize performance impact. The gem integrates seamlessly with Rails, allowing you to block spam at the request level and redirect flagged users to a captcha page.

reCAPTCHA was too much for us, so we created this. Simplest captcha ever.

Drop in feedback engine with customizable fields, and captcha available

Quick little arithmetic plain-text captcha

DeathByCaptcha allows you to solve captchas with manual labor

Rack middleware Captcha verification using Recaptcha API.

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.

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.

Captcha generator for rails

dongsx

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

TwoCaptcha allows you to solve captchas with manual labor