Spin-Transfer Torque Magnetic Tunnel Junctions (STT-MTJ) are devices featuring stochastic properties. They are promising candidates for non-volatile memory or true random number generators. To design reliable hybrid CMOS circuits including STT-MTJs, one needs to use a compact model accounting for its stochasticity in the circuit simulations. This paper proposes a compact model that accurately mimics the MTJ stochastic switching behavior and meets the needs of fast execution time. The relevance of such a model together with its fast execution velocity are illustrated with a bitstream generator.