Grating coupling for surface-emitting intersubband light-emitting diodes (LEDs) and lasers are analyzed with a numerical method. The grating efficiency is calculated as functions of the grating periodicity and filling factor, and the vertical confinement thickness. The coupling loss is related linearly with the grating efficiency, which should be maximized for LEDs to couple out the spontaneous emission, but kept low for lasers to reduce the lasing threshold. ©1997 American Institute of Physics.