Inspired by Airbnb blog post https://medium.com/airbnb-engineering/large-scale-payments-systems-and-ruby-on-rails-bfe5b89f6f4 - by including a module in any of your classes, you can validate the type and presence of a method's parameters.

Validates the given string

Provides a clean DSL to validate params for controller actions.

EachValidator that adds a parent model's association's validation errors to the parent model

Validates CNPJ and test it with matchers in a simple way.

Brazilian zipcode validations for ActiveRecord, integrated with correios-cep gem.

The purpose of this gem is to validate countrycodes in ISO 3166-1 alpha-2 format

Validates CPF and test it with matchers in a simple way.

Validates CURP and test it with matchers in a simple way.

ActiveRecord callback which handle the name duplication in your model.

Validates Host, Domain and IP and test it with matchers in a simple way.

Validates IPv4 and IPv6 addresses

Rails plugin that provides a validates_ip_format_of method to ActiveRecord models. IPs are validated by regexp. IP validation. Validate IP.

To prevent noobs from being uber noobs

This gem unions a server-side ActiveModel password strength validation plugin with a client-side password strength estimation

Validate specific value for Rails

Validate phone numbers against E.164 format with this Ruby on Rails gem

Validate against blacklist of words

Add to Rails the possibility to validate the quantity of an associate model

Validates mexican RFC and test it with matchers in a simple way.