Multi-wavelength flux light curve (left y-axis) of GRB 230812B obtained from Fermi/LAT (0.1–100 GeV), Fermi/GBM prompt (8 keV–40 MeV) and afterglow (40–400 keV), Swift/XRT (0.3–10 keV), and optical (r′) and radio (at various frequencies ranging from 1.2 to 75 GHz) telescopes. The GBM afterglow data is rescaled by a factor of 0.1 for plotting purposes. The faint data points correspond to fluxes obtained from finer time binning. The r′-band data show the optical afterglow and the emission from the associated SN. The solid lines corresponds to the best fit power-law model, F = F₀(t − T₀)^−Γ_t for afterglow data from each instrument. For each instrument, the time interval used for the fit, along with the power-law index obtained as a result, is given in Table 4. The grey solid curve shows the count-rate light curve with rates depicted by the right y axis.