The wedge-splitting test is a novel procedure for measuring fracture properties in quasi-brittle materials, such as ceramics, rocks and concrete. Stress intensity factors, for most of the practical wedge-splitting geometries, have been computed and are presented in this paper in analytical and graphical form. The stress intensity factors were numerically computed using the finite element method. Mesh objectivity and some other aspects in relation to computational precision are considered. The behaviour of the stress intensity factor for deep and shallow cracks was analyzed taking into account the asymptotic trends in both cases. An expression for the stress intensity factor-valid for all crack sizes and for usual geometries—is given.