The presence of non-existent or inactive addresses can significantly reduce your domain reputation, lead to your emails being marked as spam, and stop campaigns.

1. Checking for Typos in Addresses

If your email address database was collected manually, for example, from offline forms or registration forms, there is a high probability of typos. Even one error in an address can make it invalid.

  • Manual checking. When collecting addresses, try to manually check each entry to ensure there are no obvious errors. For example, to avoid attempting to send to addresses like @gmail.con or @out1ook.com — these are very common errors caused by simple inattention.
  • Automatic checking. Use autocomplete and validation tools when entering addresses in forms on your website. This will help reduce the number of input errors.
  • Special scripts and programs. Use scripts or programs that automatically check email address format and identify obvious errors, such as missing characters or incorrect domain suffixes.

2. Checking the Database Using Email Validators

For final quality checking of your database, it is recommended to use special services — email validators. They will help you identify not only typos but also deactivated or blocked addresses.

  • Validator capabilities. Modern validators can check address structure, domain existence, mailbox availability, and other important parameters.
  • Checking process. Upload your database to the selected validator and get a report with checking results. The service will indicate non-existent addresses, addresses with errors, and potentially risky addresses (for example, temporary or suspicious ones).

3. Excluding Old Addresses That Have Not Opened Emails in Campaigns for a Long Time

Over time, part of your audience may become inactive. This can happen for various reasons: users changed addresses, lost interest in your campaigns, or simply do not open your emails. In some services, if a user has not accessed their mailbox for a long time — it is deleted and sending to such an address will result in an error. To prevent non-existent addresses from spoiling statistics and reducing sender reputation, it is important to regularly check and clean your database.