Dependence of the stellar mass error (log(M_star/M_⊙)_err) on the stellar mass (log(M_star/M_⊙)) for two main DESI types: GALAXIES (left panel) and QSOs (right panel). The stellar mass uncertainties depend on the S/N of the optical (igrz) photometry (left panel) as well as on the S/N of the WISE photometry (right panel). The low errors (log(M_star/M_⊙)_err ≲ 0.25) are achieved when at least 3 optical bands are observed with S/N ≥ 10 and at least 3 WISE bands are measured with S/N ≥ 7.