Interaction-based content configuration is described. In one or more implementations, interactions of an online store customer with an online store are tracked. When a shopping session is ended and an item viewed during the shopping session is not purchased, personalized marketing content is generated for the customer. To do so, the tracked interactions are analyzed to ascertain which content corresponding to the unpurchased item the customer focused on during the shopping session. The tracked interactions track a gaze of the customer relative to displayed content of the online store, for instance. Further, the content the customer focused on is determined as that which held the customer's gaze for a period of time or which the customer gazed at a greater number of times than other content. The personalized marketing content is configured to include a portion of the focused-on content.