AbstractStress intensity factors are calculated in weighted average at the surface and the deepest point of a circular‐fronted surface crack in a cylindrical bar by use of the weight function method. A wide range of various crack shapes are studied, from a nearly straight‐fronted edge crack to a semi‐circular crack front. Use of the weight function method requires that the crack opening displacement field of a reference load has to be known. It was obtained by 3‐D finite element analysis. Results are presented for the cracked cylinder subjected to a constant stress (tension) and a linear stress distribution acting perpendicular to the crack faces and they are compared with values found by other invest