Optical coordinate measuring is a highly functional tool for application in metrology laboratories, in areas of quality control and reverse engineering due to its versatility in terms of non-contact measurements. However, with the increasing requirements for high accuracy results in these areas, it is necessary to guarantee the traceability of this type of equipment using standards with compatible uncertainty. In order to provide traceability to these measurement systems, this research shows a method for calibration of dimensional length standard in image metrology. In this way, two lasers are used to measure the displacement of x- and y-axes simultaneously and the measurement values are applied in a mathematical model together with pixel positions from the images of a standard. The methodology shows advantages using high magnifications to visualize the standards, showing in each image just a small part of the area. The method provides uncertainties around 0.10 μm, showing that this method is capable of providing traceability for this kind of standard.