Despite the evident success of conventional one-dimensional (1D) bar codes and their role in automatic product identification, logistics, supply, and retail, these 1D technologies can encode only a limited amount of data and are susceptible to damage and obscuration. On the other hand, two-dimensional (2D) codes which began appearing in the 1980s are becoming more and more popular because of their ability to encode a large amount of data in a small area. They can also be read even if they are partially damaged or erased. Because of their advantages in comparison to linear bar codes and their increasingly frequent use the authors analyzed two 2D codes (DATA MATRIX code and QR code). The purpose of our research was to determine the lowest raster tone value for each printing color and each printing technique which would enable the 2D code reading with two different readers. For testing the readability of codes, lightfastness, accelerated aging, and water resistance were used. Codes were created and printed in four process inks (cyan, magenta, yellow and black), each of them in the following raster tone values: 15%, 20%, 25%, 30%, 50%, and 100%. Samples were printed using three different digital printing technologies (ink jet, laser, and magnetography). After printing, the samples were illuminated by Xe light, exposed to accelerated aging (at 80°C and 65% relative humidity) for six days, and immersed in water to determine their water resistance. All printed samples, before and after illumination and accelerated aging, were read with laser and charge coupled device based readers, and the lowest raster tone value of the code for each printing technique and each printing ink was determined.