Our fingernails are also made up primarily of dead cells, a horn-like material called keratin. Growth takes place in the martix, the hidden part of the nail under the cuticle. The older cells die and harden as they are pushed out. The matrix also includes the lunula, the whitish half-moon area at the base of the nail. Fingernails grow about 0.1 mm per day or 1-2 inches a year.
Fingernails grow faster than toenails.
Nails in men grow faster than in women. The nails on the dominant hand grow faster than on the other hand. In the summer nails grow faster than in winter. Shidhar Chillal of Poona, India had a total length of 158 inches of nails on his left hand. They were uncut for 35 years.