This archive contains the numerical data underlying Figs. 4 and 5 of the manuscript “Magnetotransport across Weyl semimetal grain boundaries.” The dataset provides magnetotransport results obtained using both full-quantum (Kwant) simulations and semiclassical Landauer–Boltzmann calculations. All data are stored in HDF5 (.h5) format. Each file corresponds to a single curve in the manuscript and is named to indicate the associated figure and the relevant physical parameters (e.g., disorder correlation length ξ or disorder strength W). Every HDF5 file includes a one-dimensional dataset (T or G) containing transmission or magnetoconductance values, the corresponding magnetic-flux axis (flux), and a complete set of metadata (ξ, W, interface hopping t, Fermi energy E, and a short note indicating the corresponding figure in the manuscript) stored as HDF5 attributes.