First principles density functional calculations within the Cambridge Serial Total Energy Package (CASTEP) code applied to widely explore structural, mechanical, electronic and optical properties of MFe₂O₄ (M = Zn, Cu, Si) ferrites at pressures 0, 5, 10, 15, 20 GPa. The computed X-ray diffraction patterns showed that the lattice parameter values for MFe₂O₄ (M = Zn, Cu, Si) ferrites were 8.48-8.08 Å, 8.32-8.14 Å, and 8.23-7.87Å, respectively at external pressure 0–20 GPa. The energy bandgap of the MFe₂O₄ (M = Zn, Si) ferrites revealed a direct nature within the range 1.24-0.0.82 eV and 3.843–3.484 eV versus 0–20 GPa external pressure, respectively. The CuFe₂O₄ ferrite exhibited indirect bandgaps ranging from 1.167 to 0.992 eV versus 0–20 GPa external pressure. Hence, all the computed values of the band gap showed an inverse response to applied pressure. Mulliken population and the total density of state confirmed that all the bonds Fe–O, Zn–O, Si–O, and Cu–O were covalent. The mechanical properties revealed the cubic stability of MFe₂O₄ (M = Zn, Cu, Si) ferrites. So, these ferrites proved potential candidates in electrochemical applications. The B/G values presented that the MFe₂O₄ (M = Zn, Cu) ferrites were ductile and considered suitable candidates in photocatalytic applications. In contrast, the SiFe₂O₄ ferrite exhibited brittle behavior at all the values of external pressure 0–20 GPa and was deemed helpful to optoelectronic devices. The optical properties showed that MFe₂O₄ (Zn, Cu, Si) ferrites showed excellent photosensitivity to visible light in photocatalytic, solar cells and optoelectronic applications.