A compliant thumb wheel assembly coupled to a caliper jaw that moves along a caliper scale member along a measuring axis direction in a caliper comprises a thumb wheel, a compliant element, and a thumb wheel mounting portion rigidly coupled to the caliper jaw. The compliant element is configured to locate the thumb wheel in an operational arrangement for driving the caliper jaw while at the same time transmitting forces between the thumb wheel and the thumb wheel mounting portion by elastic deformation. When a force is applied to the thumb wheel along the measuring axis direction, the compliant element flexes such that the thumb wheel displaces along the measuring axis direction relative to the thumb wheel mounting portion and the caliper jaw, and generates a measuring force that depends on that relative displacement and which is applied to the caliper jaw along the measuring axis direction.