We find minimum sized Spherical Tokamak (ST) configurations capable of Q∼1 (scientific break-even) and ignition. For Q∼1 cases, we normalize our models to the JET device. We find comparable plasma power balance performance in an ST configuration of major radius ∼ 0.7 m, using both global and 3/2 D plasma transport modeling. For ignited plasma, we first normalize the plasma modeling to the ITER device. We find similar ignited plasma performance capabilities in an ST configuration of major radius 1.2 m. These are much smaller size plasmas than the standard tokamak counterparts, indicating a potentially easier path towards commercial applications. Also, we find that the quantity IA is not a good figure-of-merit for comparing performance of widely different tokamak configurations.