We present ESpinS (Esfahan Spin Simulation) package to evaluate the thermodynamic properties of spin systems described by a model Hamiltonian. In addition Heisenberg exchange term, Hamiltonian in can contain interactions such as bi-quadratic, Dzyaloshinskii–Moriya, and single-ion anisotropy. By applying classical Monte Carlo simulation, simulates behavior with respect temperature. calculate spe...