In order to avoid extensive and expensive testing of the JR crack resistance behavior of reactor pressure vessel steels, different correlations between the upper shelf energy obtained from Charpy impact tests and the crack resistance curve have been proposed in the literature. To analyze their applicability and the amount of conservatism, the most important correlation formulas have been compared with measured JR-curves for different German reactor pressure vessel steels. For these materials, an alternative customized correlation is proposed. All correlations investigated are found to provide reliable and conservative estimates of the crack resistance curves for temperatures up to 300 °C.