An apparatus and method for measuring substrate media thickness including a nip assembly having a first nip for engaging substrate media and transporting the media along a process direction. The first nip has a nip velocity. A sensor is in operative communication with the first nip for sensing the nip velocity. A processor is operably connected to the sensor. The processor determines a media thickness responsive to a change in nip velocity detected by the velocity sensor upon entry of the media in the first nip.