Abstract: A printability gauge which make it possible for an observer by visual inspection of the gauge to determine the degree to which the dimensions of a printed bar code symbol deviate from the dimensions of an ideal bar code symbol defined by bars and spaces whose dimensions are derived from a unit bar of predetermined thickness. The gauge includes a checkerboard pattern whose black and white squares are all of the same size only when the thickness of the unit bar in the printed symbol matches that of the ideal symbol whereby the checkerboard pattern then appears to the observer to be 50 percent gray. Should the unit bar in the printed symbol, as a result of a processing error, be thicker than in the ideal symbol, then the size of the black squares will be correspondingly enlarged at the expense of the white squares, and the checkerboard pattern will then appear to be more than 50 percent gray.