Email Address Validation Tool 15. August 2008ComputingWebvet I have been doing do a lot of email marketing lately. Our email marketing service does a pretty good job at removing records with an invalid email address from the imported data set. However, some invalid addresses still slip through and cause unnecessary bounces and license costs. We therefore need to correct or remove all invalid addresses before we import them. Some can be easily corrected without involving the subscriber, like someone@hotmail someone @ yahoo.com someone@gmail.cmo Others can be removed from the subscriber list because they originate from fake subscriptions, like test@justtesting. I was looking for an online tool to clean up an email address list but could only find tools that process one address at a time. So I read RFC 3696 to learn more about valid email address formats and wrote my own. The tool does email format checks for most of the RFC requirements. It also queries the email domain’s DNS server to look for MX and A records. UPDATE Feb 13, 2006: The email address validation tool on this page is no longer supported.