Kick spam with a highly advanced email validation in comment forms, user registration and contact forms using Mailgun's Email validation service.
Most email validators look for an
@ and a
.(dot) some go further and blacklist certain domain names. But Mailgun's Advanced email validation service goes deeper and looks for the existence of the domain name, presence of a MX record and the custom ESP(Email Service Provider) grammar.
The grammar here is the rules defined by each email provider. For example, Yahoo Mail addresses can only contain letters, numbers, underscores, and one period.
firstname.lastname@example.org perfectly passes the is_email() function but can never exist as it contains more than one period. Such addresses can't escape Mailgun's Email validation.
email@example.com't get away.
This plugin requires a Mailgun Public API Key which can be obtained through a free sign-up at Mailgun(No credit card required).
If you're trying out this plugin on a local WAMP/LAMP/MAMP installation make sure your system is connected to the Internet for this plugin to contact Mailgun.
Read about Mailgun's email validation service.