How does Gmail determine placement?

Gmail placement relies heavily on machine learning and engagement:

User engagement: Personal history with sender weighs heavily. Opens, clicks, replies build positive reputation. Ignores and spam reports build negative.

Sender reputation: Domain and IP history at aggregate level.

Authentication: SPF, DKIM, DMARC must pass and align.

Content analysis: Pattern matching against known spam signatures.

Behavioral prediction: ML models predict whether this specific user will want this specific message.

Gmail is sophisticated and continuously learning. What works today may not work tomorrow as models adapt.

Gmail's harbor master has an excellent memory and learns from every ship that enters.