To prevent noobs from being uber noobs

ActiveModel validator that ensures Word-tags hasn't been accidentally pasted into WYSIWYG attributes.

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

Validate Your Social Security Number

Add common validations.

Subdomain validator

This library helps validate that an attribute is a subset of a specified set

ValidatesTimeliness mongoid ORM compatability.

Parse numbers suffixed with mangitude specifiers and/or abbreivations.

Library for validating unchangeable attributes.

Validates if an attribute has a valid xml content or a xsd valid content.

Validate XML against it's embedded XSI elements that define the XSD's.

Adds validation methods considering different country zip code formats. Currently, we can validate 130 countries.

Delegates validation between objects

Find and report ActiveRecord validation errors.

Hints for validation.