Systems and methods are described for improving gaze estimation based on glints. An example method may be executable to receive glint-location data indicating a location for each of one or more glints that are reflected from an eye. The glint-location data may be captured by an imaging device that is attached to a head-mountable display (HMD). The method may be further executable to determine a plurality of normalized pupil locations comprising at least a first and a second normalized pupil location. Each normalized pupil location may be determined based on the glint-location data for a different combinatoric subset of the one or more glints. The method may be further executable to determine a regression model to fit the plurality of normalized pupil locations to an expected gaze location, and perform a gaze-tracking process based on the regression model.