The incredible optical, structural, and electronic behaviors of inorganic type perovskite compounds have recently attracted considerable interest in the area of solar innovation. This study thoroughly investigated how it affects both tensile and compressive strain on the physical, optical, as well as electronic behaviors that exist in the cubic inorganic Ca3NI3 perovskite using FP-DFT, or first-principles density functional theory. The planar structure of the unstrained Ca3NI3 molecule at the location revealed a direct bandgap of 1.077 eV/1.61 eV using the PBE/HSE technique. The bandgap of the Ca3NI3 perovskite was reduced to 0.827 eV by taking into account the impact of spin-orbit coupling (SOC). Additionally, the bandgap of the framework showed a tendency to decrease under compressive pressure (0.932 eV in −4% strain) and slightly increase under tensile strain (1.187 eV in +4 % strain). According to an analysis of the band characteristics, visible light can be significantly absorbed by the substance as shown by optical parameters like absorption coefficients, reflectivity, dielectric functions, and electron loss functions. The static dielectric constant, ε1(0) of Ca3NI3 is 6.96, the location of the initial critical point in, ɛ2(ω) is 1.07 eV, the energy range of the large absorption peak is 7.2–7.6 eV, peak location of loss function is 8.7–9.3 eV and reflectivity at 0 eV is 4.8. The Ca3NI3 dielectric constant spikes shifted to lower photon energy as a result of a redshift brought on by an increase in compressive strain. On the other hand, as tensile strain increased, the material showed a blue shift, resulting in an increase in photon energy. Finally, using the SCAPS-1D simulator, the photovoltaic (PV) performance of novel Ca3NI3 absorber-based cell architectures with SnS2 as the Electron Transport Layer (ETL) was thoroughly examined under varied compressive and tensile strain. The greatest power conversion efficiency (PCE) was found to be 31.35 % with JSC of 39.43 mA/cm2, FF of 85.47 %, VOC of 0.9301 V for maximum 4 % tensile strain. These findings suggest that the Ca3NI3 perovskite may be suitable for solar cell applications including energy production and light management in near future.