Introduction <p>This work explores a cantilever beam-based energy harvester structure to establish design guidelines for low-power and low-frequency applications.</p> Objectives <p>The aim of this study is to identify optimum design parameters that balance resonant frequency, device volume, and output power for target applications such as IoT, biomedical devices, and consumer electronics.</p> Methods <p>The cantilever beam structure is modelled and simulated using COMSOL Multiphysics. Performance metrics including output power, voltage, and resonant frequency are analysed for varying structural parameters. The design space is restricted to a device volume of 2063–4366 mm³ and a weight of 38–64 g. Simulation-based analysis is performed to draft design guidelines, eliminating the need for trial-and-error approaches.</p> Results <p>The study provides a correlation between structural design parameters and performance metrics, resulting in a practical design lookup table for engineers. Simulations reveal output voltage in the range of 3–300 V, output power from 64 μW to 455 mW, and resonant frequencies between 2.2–7.6 Hz. These results confirm the suitability of the proposed structures for low-frequency energy harvesting.</p> Conclusion <p>The proposed guidelines enable designers to rapidly select optimal structural parameters for specific low-frequency applications without exhaustive iterations. This approach accelerates development cycles and improves device performance predictability.</p> Novelty <p>Unlike conventional trial-and-error methods, this work presents physics-based, simulation-derived design guidelines for cantilever beam energy harvesters, tailored for constrained volume and weight ranges, with applicability to IoT, biomedical, and consumer electronics domains.</p> Graphical Abstract <p></p>