How far from the gutter, how far from the pew
The growing part of the nail is the part still under the skin at the nail’s proximal end under the epidermis, which is the only living part of a nail.
In mammals, the length and growth rate of nails is related to the length of the terminal phalanges (outermost finger bones). Thus, in humans, the nail of the index finger grows faster than that of the little finger; and fingernails grow up to four times faster than toenails.
In humans, nails grow at an average rate of 3 mm (0.12 in) a month (as they are a form of hair). Fingernails require 3 to 6 months to regrow completely, and toenails require 12 to 18 months. Actual growth rate is dependent upon age, gender, season, exercise level, diet, and hereditary factors. Nails grow faster in the summer than in any other season.
Contrary to popular belief, nails do not continue to grow after death.