This document defines a method of determining bulk density of solid biofuels by the use of a standardized measuring container. This method is applicable to all pourable solid biofuels with a nominal top size of maximum 63 mm while the maximum particle length is 200 mm. For fuels with a nominal top size larger than 63 mm, a different method is described. Bulk density is not an absolute value; therefore, conditions for its determination have to be standardized in order to gain comparative measuring results. NOTE Bulk density of solid biofuels is subject to variation due to several factors such as vibration, shock, pressure, biodegradation, drying, and wetting. Measured bulk density can therefore deviate from actual conditions during transportation, storage, or transhipment.