Abstract The Finite element analysis (FEA) plays a vital role for the design and development of microdevices, which provides the solutions to understand the behaviour virtually for the optimization of specific device. In the present work, we designed two different energy harvesting (EH) models with variable dimensions and analyzed the EH performance for wide range of pressure. The proposed models consist of four piezoelectric microcantilevers coupled with square (Design-I) and circular (Design-II) shaped micro-membranes. The piezoelectric material PZT-5H was used as transduction material and the gold electrodes were used as charge collector. The EH designs (I & II) were modelled with variable membrane thickness viz., 1 µm and 0.5 µm and their output performances like total displacement, von Mises stress, volumetric strain and electric potential were studied for the pressure range of 200–2000 Pa. The EH design-I generated the maximum output potential of 167 µV (1 µm) and 186 µV (0.5 µm) for the applied pressure of 2000 Pa. Similarly, EH design-II generated the maximum output potential of 138 µV (1 µm) and 174 µV (0.5 µm) for the applied pressure of 2000 Pa. Relatively, the EH designs I & II with 0.5 µm thickness exhibited best output performance for the maximum applied pressure of 2000 Pa, which generated maximum output potential of 186 µV and 174 µV, respectively. In comparison with the other designs, the piezoelectric microcantilever coupled with square shaped micro-membrane (Design-I) of 0.5 µm thickness exhibited better EH performance than the circular shaped micro-membrane (Design-II).