This work mainly focuses on synthesizing and evaluating the efficiency of methylammonium lead halide‐based perovskite (MAPbX3; X=Cl, Br, I) solar cells. We used the colloidal Hot‐injection method (HIM) to synthesize MAPbX3 (X=Cl, Br, I) perovskites using the specific precursors and organic solvents under ambient conditions. We studied the structural, morphological and optical properties of MAPbX3 perovskites using XRD, FESEM, TEM, UV‐Vis, PL and TRPL (time‐resolved photoluminescence) characterization techniques. The particle size and morphology of these perovskites vary with respect to the halide variation. The MAPbI3 perovskite possesses a low band gap and low carrier lifetime but delivers the highest PCE among other halide perovskite samples, making it a promising candidate for solar cell technology. To further enrich the investigations, the conversion efficiency of the MAPbX3 perovskites has been evaluated through extensive device simulations. Here, the optical constants, band gap energy and carrier lifetime of MAPbX3 were used for simulating three different perovskite solar cells, namely I, Cl or Br halide‐based perovskite solar cells. MAPbI3, MAPbBr3 and MAPbCl3 absorber layer‐based devices showed ~13.7 %, 6.9 % and 5.0 % conversion efficiency. The correlation between the experimental and SCAPS simulation data for HIM‐synthesized MAPBX3‐based perovskites has been reported for the first time.