Glossary / Sender reputation
What is Sender reputation?
Sender reputation is the score mailbox providers keep on you, based on how people react to your email. It decides inbox or spam folder.
Gmail, Outlook, and the rest watch every sender. They track your domain and sending address, then build a picture from how recipients behave: opens, replies, deletions without reading, and spam complaints.
Bounces to dead addresses hurt. Spam complaints hurt much more. Sudden volume spikes look suspicious too, which is why careful senders warm up a new domain slowly instead of blasting 50,000 emails on day one.
Reputation is slow to build and quick to lose. Recovery means cutting volume, sending only to your most engaged contacts, and rebuilding the signal over weeks. There is no reset button.
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