The service class of a crane is one of the key parameters in crane design and can be determined according to various standards. In domestic practice, the classification according to the JUS M.D1.020 standard was prevalent for a long time, defining four crane service classes based on the number of working cycles and operating time. In the past, many renowned crane manufacturers based their classification on the DIN 15020 standard, which is predicated on FEM (Fédération Européenne de la Manutention) guidelines (which consider operating time and load spectrum as the dominant classification parameters). Older versions of ISO standards are also closely linked to FEM guidelines and provide service classes equivalent to these recommendations. With the introduction of the EN 13001 series of standards and ISO 4301-1:2016, the number of operating cycles has a more significant impact on crane classification. Unfortunately, in domestic engineering practice, the newly adopted standards for industrial cranes are still not widely applied due to various uncertainties. The aim of this paper is to resolve certain uncertainties regarding the definition of crane service classes and to present, in a concise form, a comparison and the relationship between parameters according to current standards and guidelines. A brief overview of the withdrawn JUS M.D1.020 standard is also included.