Method for calibrating a head-mounted eye tracking device, the method comprising: - an acquisition step, during which eye data relating to the position of the eye of the wearer are acquired by the eye tracking device while having the wearer of the head-mounted eye tracking device look in a direction of reference, - an association step during which the eye data acquired during the acquisition step are associated with the gaze direction corresponding to the direction of reference, - a recording step, during which the associated eye data and the gaze direction are recorded, wherein the head-mounted eye tracking device comprises a spectacle frame in which ophthalmic lenses are mounted and the gazing direction corresponding to the direction of reference is determined based on the dioptric function of the ophthalmic lenses, and in that the method further comprises prior to the acquisition step: - a calibration support providing step, during which a calibration support comprising at least a visual reference element is provided to a wearer wearing the head mounted tracking device, and - a placing step, during which the calibration support is placed between at least one eye of the wearer and the visual environment of the wearer in a known position relative to the wearer's eye and to the eye tracking device so as to define with the visual reference element a direction of reference, wherein during the placing step the calibration support is placed on at least one of the surfaces of at least one of the ophthalmic lenses and the gazing direction corresponding to the visual reference element is determined based on the dioptric function of the ophthalmic lenses. - an acquisition step, during which eye data relating to the position of the eye of the wearer are acquired by the eye tracking device while having the wearer of the head-mounted eye tracking device look in a direction of reference, - an association step during which the eye data acquired during the acquisition step are associated with the gaze direction corresponding to the direction of reference, - a recording step, during which the associated eye data and the gaze direction are recorded, wherein the head-mounted eye tracking device comprises a spectacle frame in which ophthalmic lenses are mounted and the gazing direction corresponding to the direction of reference is determined based on the dioptric function of the ophthalmic lenses, and in that the method further comprises prior to the acquisition step: - a calibration support providing step, during which a calibration support comprising at least a visual reference element is provided to a wearer wearing the head mounted tracking device, and - a placing step, during which the calibration support is placed between at least one eye of the wearer and the visual environment of the wearer in a known position relative to the wearer's eye and to the eye tracking device so as to define with the visual reference element a direction of reference, - a calibration support providing step, during which a calibration support comprising at least a visual reference element is provided to a wearer wearing the head mounted tracking device, and - a placing step, during which the calibration support is placed between at least one eye of the wearer and the visual environment of the wearer in a known position relative to the wearer's eye and to the eye tracking device so as to define with the visual reference element a direction of reference,