Abstract: A carpet trimmer comprising a base plate with slots directed at right angles to the working edge of the base plate. Underlying the base plate is a post holder with upstanding threaded posts protruding through the slots of the base plate. Overlying the base plate is a blade holder that engages the posts for movement with the post holder. Suitable nuts on the posts lock the post holder and the blade holder in an adjusted position relative to the base plate. A wall guide depends from the blade holder in spaced relation to the working edge of the base plate to define a passageway for a carpet edge to be trimmed by blades on the blade holder. When the nuts are loosened, the posts can be moved within the slots of the base plate toward or away from the working edge of the base plate. In so doing, the post holder and the blade holder move therewith. This action adjusts the distance between the working edge of the base plate and the wall guide to accommodate different thicknesses of carpets.