Abstract: An apparatus includes a body member which has a pair of guide surfaces. A blade projects from a first of the guide surfaces and the cutting edge of the blade forms an acute angle with the first guide surface. The plane of the blade forms an acute angle with the second guide surface thereby facilitating a clean cutting action. The angle of the plane of the blade maintains contact between the guide surfaces and the carton being opened and minimizes any tendency for the carton opener to leave the cut. The body member includes a curved portion forward of the blade and a projecting wall portion which serves to position the hand of the user in the correct ergonomic position for safe and efficient operation.