A raytracing facility for evaluating soft x‐ray and vacuum ultraviolet optics, especially synchrotron radiation monochromators and beamlines, has been reported. Such kinds of optics consist of any number of reflecting mirrors, gratings, and, if needed, stop apertures: in coplanar or orthogonal configuration; conventional, holographic, and varied line‐space gratings are available dispersing elements in design of a monochromator. Both normal and grazing incidence optics can be handled well. Point or finite sources, necessary to be setup in the raytracing process, may be used of isotropic or of Gaussian distribution. The spot diagram or grey level image simulation will be produced. Finally, an example of its applications, raytracing of a Seya–Namioka monochromator beamline at NSRL, will be presented. © 1994 American Institute of Physics.