A method for determining the skew of a printhead of a printer. At least three images are printed which are at least partially aligned substantially along the printhead scan direction with the middle image printed from one of the upper and lower portions of the printhead and with the adjacent images printed from the other of the upper and lower portions of the printhead. A sensor is moved in the printhead scan direction over the images. A function is calculated from the sensor output, wherein the calculated function indicates the skew of the printhead.