The addition of aluminum powder to the explosive reduces the maximum value of the pressure impulse while significantly increasing the duration of the pressure impulse coming from the detonation of the explosive. The purpose of the conducted research was to determine and compare TNT equivalents of charges made of HMX explosive without and with the addition of aluminum powder. TNT equivalent is used in many cases when studying the effects of a blast wave impulse on a structure. Experimental tests were carried out using: fabricated explosive charges without and with aluminum powder, a ballistic pendulum and high-speed cameras. Based on these, the effects of the pressure wave on a structure were determined in the form of the time course of the pendulum’s tilt. The course of the phenomenon was then reflected using an explicit implementation of the finite element method in the Ls-Dyna Ansys program. In the case of numerical analyses, the ConWep algorithm was used, which allows the use of TNT equivalent for the analysis of the pressure wave’s effect on the structure. By trial and error, the values of the equivalent were chosen to represent the experimental course of the pendulum tilt as accurately as possible. In both analyzed cases, a very high agreement was obtained between experimental results and numerical analyses. The value of the TNT equivalent in the case of a load with aluminum powder was 20% higher, than without the addition.