Email Addresses Verification In Bulk Via DataValidation API

  • Post published:August 17, 2015

Email marketers often encounter common problems related to invalid email addresses in a bulk. Sometimes, many servers apply certain restrictions on a web application and due to the presence of invalid email addresses in the bulk list, it can block the email sending process. Doing so repeatedly can end up in a complete process blockage.


Our Client’s web application also maintains a bulk list of email addresses. Emails need to be send very frequently to this bulk list email addresses. The same issue occurred due to the presence of invalid email addresses in the list. Sending emails frequently on invalid email addresses completely blocked the email sending process.

To resolve this issue, a module was required from vteam #398 to provide a solution which can check the validity of email addresses present in the mailing list so that a clean list of valid email addresses can be achieved.


vteam #398  did some R&D and found DataValidation API as a suitable verification tool for the above mentioned problem. DataValidation API receives an email address, validate it and provide the result with information whether it is a valid email address or invalid email address or unknown. There is a fee of using DataValidation API and this fee depends on the number of email addresses sent for validation. More the email addresses sent to DataValidation API for validation, higher would be the price. In order to reduce the fee, we applied additional email format checks which are performed on email addresses prior sending to DataValidation API so that it can be checked whether an email address is valid or not without using DataValidation API. These checks included the following:

  • Email address should be in a proper format
  • There should be symbols like ‘@‘ and ‘.‘ (dot) in email address
  • Same email address should not be sent to DataValidation API multiple times for its validation

For further cost optimization purpose, we developed a policy that when an email address is sent to DataValidation API, its result from DataValidation API should be stored in the Database. Next time before sending any email address to DataValidation API, Client should check the history whether this email address already been checked by DataValidation API or not. If it has already been checked then there would be no need of sending that email address again and again for validation. As a result of this, we would have assured email delivery and verification of email addresses while maintaining the cost to a lower level.