A device for measuring the radius of curvature of a surface comprises a main body that is held above the surface being measured; and a non-contact sensor mounted to the main body that measures a distance between the surface being measured and the sensor, the device calculating the radius of curvature of the surface based on the measured distance. The device can further include a display mounted to the main body that displays the calculated radius of curvature. The non-contact sensor can be, for example, an acoustical distance sensor or an optical distance sensor. In one embodiment, the device includes two arms extending from the main body of the device and being substantially symmetric about the non-contact sensor, the arms terminating in contact points that make contact with the surface being measured. In another embodiment, the device includes three non-contact sensors mounted to the main body, each measuring a distance between the surface being measured and the respective sensor, the device calculating the radius of curvature of the surface based on the measured distances. In yet another aspect of the invention, a radius of curvature measuring device has an adjustable arm that is movable with respect to a main body and a linear encoder associated with the adjustable arm for measuring a distance from the surface of interest.