International audienceCircular-fronted cracks in round bars subject to tension, bending and twisting are considered. Numerical expressions are given allowing the calculation of stress intensity factors $K_I$, $K_{II}$, $K_{III}$ at every point on the crack front for a wide range of crack geometries. Comparisons are made with analytical, experimental and numerical results available in the literature. Crack shapes satisfying the iso-$K_I$ criterion are also determined, making it possible to investigate the problem of crack growth behaviour under tensile or bending fatigue loads