This study investigates the free vibration behavior of smart magneto-electro-elastic functionally graded (TMEE-FG) nanosensors with porosity. The nanobeams are composed of ferroelectric barium-titanate (BaTiO₃) and magnetostrictive cobalt-ferrite (CoFe₂O₄), with four different porosity models: uniform porosity (UPM), symmetric porosity (SPM), porosity concentrated in the bottom region (BPM), and porosity concentrated in the top region (TPM). The study considers the effects of thermal stress, thermo-magneto-electroelastic coupling, electric and magnetic fields, nonlocal effects, porosity models, and porosity volume changes on the free vibration of the nanobeams. The temperature-dependent mechanical properties of BaTiO₃ and CoFe₂O₄ are analyzed, and the results show that the dimensionless frequencies are influenced by the nonlocal parameter, external electric potential, and temperature, while the slenderness ratio and external magnetic potential cause the frequencies to decrease. The porosity volume ratio has different effects on the frequencies depending on the porosity model. The study also examines the effects of various parameters such as material composition, slenderness ratio, nonlocality, linear, shear, and viscous layers of foundation, magnetic potential, electric voltage, damping coefficient, and boundary conditions on the vibration behavior of the nanobeams. The results show that the dimensionless frequencies decrease with increasing porosity volume fraction, and the effects of porosity distribution on the frequencies are significant. The study provides insights into the mechanical behavior of TMEE-FG nanobeams with porosity, which can be applied to nanoelectromechanical systems, soft robotics, wearable technology, nano drug delivery, and gas sensing. The results highlight the importance of considering temperature-dependent properties and porosity distribution in the design and analysis of smart nanosensors.This study investigates the free vibration behavior of smart magneto-electro-elastic functionally graded (TMEE-FG) nanosensors with porosity. The nanobeams are composed of ferroelectric barium-titanate (BaTiO₃) and magnetostrictive cobalt-ferrite (CoFe₂O₄), with four different porosity models: uniform porosity (UPM), symmetric porosity (SPM), porosity concentrated in the bottom region (BPM), and porosity concentrated in the top region (TPM). The study considers the effects of thermal stress, thermo-magneto-electroelastic coupling, electric and magnetic fields, nonlocal effects, porosity models, and porosity volume changes on the free vibration of the nanobeams. The temperature-dependent mechanical properties of BaTiO₃ and CoFe₂O₄ are analyzed, and the results show that the dimensionless frequencies are influenced by the nonlocal parameter, external electric potential, and temperature, while the slenderness ratio and external magnetic potential cause the frequencies to decrease. The porosity volume ratio has different effects on the frequencies depending on the porosity model. The study also examines the effects of various parameters such as material composition, slenderness ratio, nonlocality, linear, shear, and viscous layers of foundation, magnetic potential, electric voltage, damping coefficient, and boundary conditions on the vibration behavior of the nanobeams. The results show that the dimensionless frequencies decrease with increasing porosity volume fraction, and the effects of porosity distribution on the frequencies are significant. The study provides insights into the mechanical behavior of TMEE-FG nanobeams with porosity, which can be applied to nanoelectromechanical systems, soft robotics, wearable technology, nano drug delivery, and gas sensing. The results highlight the importance of considering temperature-dependent properties and porosity distribution in the design and analysis of smart nanosensors.