When registering users in the database, not all users enter a valid, functioning email address. Some users may be unwilling to provide their email and enter
a non-existent address in the profile. Others may make random errors.
It's possible that users still don't fully trust your website and are afraid of receiving irrelevant newsletters.

Subsequently, you send messages to these addresses. If the bounce rate exceeds 5%, mail services may partially or entirely block all messages from you. This means that, including legitimate and real users, won't receive messages from you.

To avoid this, it is important to monitor the quality of the email address database. If you integrate our service, we can achieve this in two ways:

• During registration in the database, perform real-time API-based verification. You can immediately inform the user that their address
  is invalid and request them to enter a valid one. This way, you will filter out the majority of invalid addresses and guarantee not to exceed
  the 5% threshold.

• For the accumulated database, conduct a check on existing users. Those identified as invalid can be unsubscribed from further communication. This operation should be repeated, especially
  if you send infrequent newsletters (as some addresses may become outdated). It is also crucial for addresses collected offline, such
  as through surveys.

What sets Cleancontact apart from others:

• We validate the majority of popular email services, such as (but not limited to) addresses ending in mail.ru, yandex.ru, gmail.com.
  These three services alone cover approximately 85% of all addresses;
• The more you validate, the more cost-effective it becomes.
  The validation cost per address decreases as the volume increases;
• We perform real-time validation through API.