Email Glossary

Delivery Rate

Delivery rate is the percentage of emails that were successfully accepted by the receiving mail server, calculated as (sent - bounces) / sent. A delivery rate above 95% is considered healthy. Note that delivery rate does not measure inbox placement, an email can be delivered but land in spam.

Delivery Rate vs Deliverability

These terms are often confused:

  • ●Delivery rate: Did the receiving server accept the email? (binary: yes/no)
  • ●Deliverability/Inbox placement: Did the email land in the inbox? (inbox vs spam vs promotions)

A 98% delivery rate with 50% inbox placement means half your delivered emails went to spam. Focus on both metrics.

Related Terms

Email Deliverability

The ability of your emails to reach recipients' inboxes instead of spam.

Bounce Rate

The percentage of sent emails that couldn't be delivered to the recipient.

Inbox Placement

Whether delivered emails land in the primary inbox, promotions tab, or spam folder.

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