A compact apparatus for analyzing a signature or other handwritten markings, including a horizontal platen which can support paper on which a signature is written, a pair of inner beams extending horizontally from opposite sides of the platen to an intermediate structure, and a pair of outer beams extending horizontally, and in directions perpendicular to the inner beams, between the intermediate structure and a supporting frame. Strain gauges are attached to the sides of the inner and outer beams to sense forces applied to the platen by the tip of a writing instrument in the horizontal "X" and "Y" directions, and additional strain gauges are attached to opposite faces of the outer beams to sense forces in the vertical, or "Z," direction.