Abstract <p>A review of papers evidencing the positive significance of the specific surface area of abrasive synthetic diamond powders and the methods of influencing the change in its value was carried out. The trends in the modern development of methods for the indirect analytical estimation of the external specific surface area as a technological property of such abrasive powders were analyzed. The methodological features of the application of extrapolation-analytical and fractional-averaging methods in determining the external specific surface area of abrasive synthetic diamond powders were studied. The comparative study of the application of these two methods to high- and increased-strength abrasive synthetic diamond powders was performed. It was established that the application of the fractional-averaging method to high-strength abrasive synthetic diamond powders makes it possible to obtain more reliable indicators of external specific surface area as compared to the extrapolation-analytical method. The degree of increase for the studied high-strength abrasive powders was changed from 1.5 to 2.35 times. The factors influencing the increase in the specific surface area were identified. Some practical recommendations concerning the validity and feasibility of the fractional-averaging method for determining the external specific surface area of synthetic diamond abrasive powders of this class were formulated.</p>