Email Validation: Introduction

Email validation service helps you reach your audience inboxes.

Sending emails to invalid email addresses incurs unnecessary costs and affects overall email messaging success. Not only it affects the campaign where you target the invalid emails, but it has a negative impact on your overall sending causing bad sender reputation. With a bad sender reputation, your messages end up in the spam folder or get blocked even earlier by email service providers. 

Email validation helps you solve these issues by uncovering bad emails, so you can clean up your recipient list. 


The syntax for an email address implies there should be a local part followed by the @ symbol and the domain part. In both the local and domain parts, there are specifications published online which determine what characters are acceptable for either one. These specifications are called “Requests For Comments (RFC)”. They are published by the Internet Engineering Task Force (IETF) and the Internet Society (ISOC), the principal technical development and standards-setting bodies for the Internet.  

On top of these rules, internationalization of both local and domain parts within the email addresses along with a custom set of rules for each mailbox provider introduces additional complexity in comprehensive email syntax validation. 

Infobip Email Validation service will eliminate the guesswork and confirm if the syntax is correct by returning ValidSyntax = True whenever you are dealing with a correctly composed email address. 


Mailbox verification 

The mailbox verification performs a check with ESP’s and returns ValidMailbox true if the email is valid and exists; false if the email is invalid or not found, or unknown if the SMTP request could not be completed. Unknown emails will also be returned if mailbox verification is not supported on the target mailbox provider. Only results having response equal to true should be treated as valid recipients. 



Typos are very common, but it is a bad reason for not connecting with your customers. The built-in suggestion service will help you overcome this and suggest a valid value instead. 


Suspicious addresses 

Messaging high-risk recipients undermine your sender reputation, identifying valid but role-based, or disposable emails help you avoid this risk. Role-based email addresses like help@ are not associated with a person but with a company, department or a group of recipients. Some of these role-based addresses are associated with high bounce rates and spam complaints so it is advisable you remove them from the recipient lists. 

Disposable emails are temporary addresses known to be used by spammers. Sending emails toward such addresses will cause your emails landing in spam folders. The disposable and RoleBased address should be avoided as recipients