Abstract: Several caliper accessories are provided that make a conventional caliper suitable for more sophisticated applications traditionally reserved for more expensive measurement devices. One of these accessories, a magnetic caliper mounting device, has a shallow scale-bar-mounting channel for receiving the scale bar of the caliper, a retainer adapted to releasably secure the scale bar of the caliper within the channel of the caliper mount, and a magnet associated with the caliper mount to secure the apparatus to a planar metal surface. Another accessory, a caliper jaw extender, is either incorporated into a magnetic caliper mounting device or provided as a spring pack accessory to a magnetic caliper mounting device. The caliper jaw extender has a spring-biased retractor that hooks onto a caliper's movable frame and biases the frame toward an extended position. Kits are also provided comprising various combinations of a conventional caliper and accessories.