Inbox placement

Inbox placement is the part of deliverability that sending tools cannot see directly. A message accepted by the receiving server counts as delivered, whether it then lands in the inbox, the spam folder or a promotions tab. To measure placement, senders use seed tests: a message goes to a set of test mailboxes at different providers, and the tool reports where it landed in each.

Seed tests are a snapshot, not a verdict. Placement differs by provider, by the recipient's own history with you and by the content of each message, so a good seed result does not guarantee that every prospect sees your email. Trends tell you more than single tests: a falling reply rate with steady volumes, rising soft bounces or a domain listed on a blocklist are all signs that placement is slipping, usually because of reputation rather than wording.