Piklist is the most powerful framework available for WordPress. Easy for beginners... built for developers. Piklist helps you build things - fast.
The Validated Field add-on for Advanced Custom Fields provides input masking and validation of other field types.
Generic form processor allowing forms to be painlessly processed and aggregated, with numerous options to validate data and perform custom commands
This plugin adds support for the required attribute in inputs in forms.
Valida campos de DNI, NIF, NIE y CIF utilizando el plugin Contact Form 7 || Validate DNI, NIF, NIE and CIF fields using Contact Form 7 plugin
Client side validation of your WordPress Comment form
Inspects and logs possible issues with your WordPress installation.
bValidator - Form validator for jQuery , bValidator is a jQuery plug-in for client side form validation.
Check if the Email's Gravatar is exist. 檢測指定郵箱的Gravatar是否存在
Validates the comments of your blog using jQuery, avoiding blank fields or invalid fields.
Create verified polls and petitions that enable users to send results to US Elected Officials, Govermt. Agencies, Corporations and 20,000 Journalists
This plugin provides the ability to run HTML Tidy through all your posts, pages, and comments, generating a report on just how dirty your code is.
Empty posts/pages still get wrapped in tags, which makes them invalid. This plugin fixes that. PHP5 Required.