To calculate the weight of H beam steel, one needs to use the relatively easy formula: Weight = Volume x Density. The volume of a H beam can be calculated by its physical attributes (height, width & length) and the density of most steel is approximated to be 490 lb/ft3 (7850 kg/m³). Construction specialists can therefore use this formula to estimate the weight of H beams, which is essential in applications that require equilibrium and the right amount of load on structures.