A moire technique for the analysis of the reconstruction accuracy and uniformity of holograms is presented. A Ronchi ruling is recorded holographically, and the image is cast on the object ruling. The superposition of the two rulings forms a moire pattern that serves for the evaluation of the holograms. Reconstruction accuracies of 0.05 percent could be monitored throughout the whole field. This moire pattern may also be applied for studying phase objects.