Abstract: A hand-held measuring device including an elongated base having a pair of opposed parallel metric measuring scales on the upper face thereof, a slider slidably mounted on the base having a linear indicator perpendicular to the axis of the base and a holder device for holding the stamp on the base under the slider while the slider is being moved from one end of the printed border on the stamp to the other. The left hand edge of the printed border of the stamp must be zeroed at the zero points of both scales using the indicator line. The slider is then slid to the opposite printed border on the face of the stamp while the holding means is held firmly so that the indicator line registers therewith. The precise dimension of the distance across the face of the stamp to the right hand printed border can then be read off of both scales. The indicator inscribed on the slider is perpendicular to the axis of the base. The holding device can be a thin flexible folded over piece of celluloid type plastic.