The spherical Jeans equation is a widely used tool for dynamical study of gravitating systems in astronomy . Here we test its efficacy in robustly weighing the mass of Milky Way analogues , given they need not be in equilibrium or even spherical . Utilizing Milky Way stellar halos simulated in accordance with \Lambda { CDM } cosmology by Bullock and Johnston ( 2005 ) and analysing them under the Jeans formalism , we recover the underlying mass distribution of the parent galaxy , within distance r / { kpc } \in [ 10 , 100 ] , with a bias of \sim 12 \% and a dispersion of \sim 14 \% . Additionally , the mass profiles of triaxial dark matter halos taken from the surfs simulation , within scaled radius 0.2 < r / r _ { \text { max } } < 3 , are measured with a bias of \sim - 2.4 \% and a dispersion of \sim 10 \% . The obtained dispersion is not because of Poisson noise due to small particle numbers as it is twice the later . We interpret the dispersion to be due to the inherent nature of the \Lambda { CDM } halos , for example being aspherical and out-of-equilibrium . Hence the dispersion obtained for stellar halos sets a limit of about 12 \% ( after adjusting for random uncertainty ) on the accuracy with which the mass profiles of the Milky Way-like galaxies can be reconstructed using the spherical Jeans equation . This limit is independent of the quantity and quality of the observational data . The reason for a non zero bias is not clear , hence its interpretation is not obvious at this stage .