Hybrid halide perovskites are an outstanding family of materials for a wide range of optoelectronic applications due to their unique optical and electrical properties. Lead-based chemicals, which are harmful to the environment, are used to attain high power conversion efficiency. Here, carried out the modeling and simulation for fundamental and photovoltaic analysis of a non-toxic formamidinium tin iodide [HC(NH2)2SnI 3] perovskite, via the first-principles method executed in WIEN-2K code with WC-GGA potential. Direct energy bandgap 1.34 eV (at symmetry point R), Optical (dielectric constants, refractive index, absorption coefficient), Elastic parameters (Pugh ratio B/G ∼ 2.21, anisotropic index A ∼ 0.54) reveals that FASnI 3 have a semiconductor nature and have broader visible absorption spectrum with mechanically stable. For the performance of photovoltaic device simulation, the AMPS-1D (Analysis of Microelectronic and Photonic Structures-one dimensional) have been used. The essential absorbance parameters, such as band gap, defect density, thickness, doping concentration, and operating temperature have been used. Furthermore, Electron transport layer (ETL) and Hole transport layer (HTL) like as, ZnO/ZnTe/ZnSe/ZnS/CdS have been investigated and calculated efficiencies are 25.3/24.2/24.4/18.1/22.5%, respectively. Additionally, for calculation of photovoltaic efficiency, the Spectroscopic Limited maximum Efficiency (SLME) metric has been used and computed efficiency is 28.37% at room temperature with 300 nm thickness. The present research offers a new perspective; which is of great impact as far as enhancement of the quality of crystallization of perovskite-based on the tin and involving the improvement of the performance of non-toxic perovskite solar cells (PSCs).