California License Plates California DMV
License Plate Sizes. Automobile, commercial, and trailer license plates are 12 x 6. Motorcycle license plates 7 x 4 plates issued prior to July 1, 1970, are 8 x 5 . Identifi ion plates issued to vehicles not bearing automobile, commercial, trailer, or motorcycle plates are 7 x 4 plates issued prior to January 1, 1981 ...