Abstract: According to the inherent relation between the crackshape and the stress intensity factor (SIF) distribution along the crack front,a gradientless iterative method is proposed for obtaining the shape and thecorresponding SIF of mode-I planar crack with a given SIF distributionfunction under the condition of Linear Elastic FractureMechanics. Numerical examples for planar cracks in through-cracked andsurface-cracked plates with limited thickness and width are presented toshow the validity and practicability of the proposed method. The effects ofvarious SIF distribution functions on the shape and the corresponding SIF ofcracks are analyzed and discussed. The presented method is shown to bean effective alternative for the evaluation of SIFs and the prediction ofshape evolution for growing cracks.