Humans have 90 to 150 eyelashes on the upper lid and 70 to 80 eyelashes on the lower lid of each eye. Eyelashes on the upper lid are longer than those on the lower lid and grow up to 10 millimeters in length.
There are three phases of growth for an eyelash: anagen, catogen and telogen. During the anagen phase, the eyelash hair grows for a period of 20 days. During the catogen phase, the eyelash stops growing and the follicle begins to shrink. The telogen phase is a phase of rest for the eyelash. It remains in this phase for approximately 100 days before falling out.