The invention relates to an indexing chuck comprising a chuck body having an opening; a pivoting ring disposed in the opening, the pivoting ring having at least three clamping jaws that can be advanced radially, perpendicular to the longitudinal axis of the chuck body; an advancing device which is disposed in the pivoting ring and by means of which the clamping jaws can be moved synchronously; and two pivot pins, supported in the chuck body and forming a pivot axis, wherein the advancing device comprises a synchronizing ring which is movable relative to the pivoting ring, a driving surface extending at an angle to the longitudinal axis of the chuck body where it contacts a clamping jaw, and a contact surface on the respective clamping jaw which interacts with the driving surface of the synchronizing ring such that the clamping jaws are moved radially.