This record contains the dataset generated by simulating the tandem solar cell. The first zip file contains the supplementary data files which includes Figure S1. Summery graph representing efficiencies of the simulated and experimental data Figure S6. Absorption profile of perovskite layer Figure S7. Charge generation rate in the tandem device. Figure S12. Power conversion efficiency as a function of front cell and back cell thickness. The second zip file contains the main text data files which includes Figure 1(d): AM1.5G spectra received by front cell and filtered spectra received by back cell. Figure 3(a)&(b): Ultraviolet photoelectron spectra Figure 6(a)&(c): Energy band diagrams