A program is developed that allows to numerically assess the area of defects in protective coatings by analyzing digital images of surfaces. The program is implemented in Microsoft Visual Studio programming environment. The possibility of estimating the area of flaking of the paint coating from the base layer (%) and determining the adhesion in points, in accordance with the cross-cut test method in the context of paint production is shown. The created program does not require a large computing power of the computer and can reduce the time to obtain calculation results for one plate with a coating from 20 minutes to 1-2 seconds. An example of using the developed program for calculating the area of metal surface areas with different chemical composition is given.