Abstract: A shingle cutter that is portable and can be temporarily attached to and used on the roof with the roofing nails used on the job. The power for cutting results from the housing of the cutting wheel being manually drawn back towards the operator. The shingle cutter has a structural base and two vertical end walls that support a rectangular rack, which holds the cutting block. In one version the rack drives a pinion, which in turn drives the cutting wheel. In a second version, the cutting wheel is free to rotate as it is pulled through the shingle. The cutting block is constrained by rollers in contact with the top and bottom of the rectangular guide bar so that the cutting wheel moves to perform a shearing function with an abutting shear ledge mounted on the structural base.