A specially designed tri-tunable pixelated metamaterial was investigated emphasizing the transmission characteristics. The top metasurface (of metamaterial) was comprised of squared pixels of SrTiO₃ and graphene mediums deposited over an indium antimonide nanolayer; the SiO₂ dielectric medium constitutes the bottom substrate. The transmission characteristics of metamaterial, along with the electrical and magnetic tuning, were artificially controlled, and therefore, the effects due to altering external stimuli, such as thermal ambience, graphene chemical potential, and magnetostatic bias, were studied. The results yielded high sensitivity resonance transmission in the THz frequency range. The ON/OFF switching states of metamaterial, as illustrated in the form of transmission spectra, supported very high (∼98  %  ) or almost vanishing transmission in the 1 to 6 THz frequency range along with the polarization-insensitive property. In addition, the response to the incidence obliquity also remained fairly stable. The results reveal the potentials of the reported metamaterial in optical sensing due to its capabilities under the thermal, electrical, and magnetic stimulations.