Techniques for characterizing nanomaterials are essential for comprehending their properties at the nanoscale, which opens up a wide range of applications in energy, electronics, and medicine. These techniques are essential for creating, adjusting, and using nanomaterials in order to safely reveal their secrets. Their main goals are to comprehend characteristics, optimize synthesis, stimulate design, guarantee quality, promote research, and spur innovation. This chapter discusses numerous methods, providing information about the structures of nanomaterials, such as thermal analysis, spectroscopy, diffraction, and microscopy. Notwithstanding obstacles such as sample artefacts and instrumentation constraints, cautious handling, technological innovations, interdisciplinary cooperation, and ethical principles are crucial. This chapter also deals in the techniques involving safety, ethical, and environmental issues while unlocking the mysteries of nanomaterials and advancing material science and technology.