An estimation method includes first acquiring information of an eyeball motion of a user on the basis of a measurement value of an eye potential of the user, second acquiring positional information of an interaction target on a screen that corresponds to an interaction performed on a device through an operation of the user, third acquiring information regarding a relative motion of sight of the user on the basis at least of the information of the eyeball motion of the user, and estimating a sight position of the user on the screen on the basis of the information regarding the relative motion of the sight of the user and the positional information of the interaction target on the screen, by processing circuitry.