Fingernails are primarily made of layers of a tough, hardened protein called keratin, specifically alpha-keratin. This protein is also found in hair, skin, animal hooves, claws, and horns. Keratin provides strength and resilience to the nails, protecting them from damage

. The visible part of the nail, known as the nail plate, consists of dead keratinized cells that are pushed out from the nail matrix, the active tissue beneath the skin that produces new nail cells. As new cells form, older cells harden, flatten, and become translucent, revealing the pinkish color of the blood vessels underneath in the nail bed

. Additional components related to the nail structure include the cuticle, which is a protective layer of dead skin cells sealing the nail plate to the fingertip, and the lunula, the whitish crescent-shaped visible part of the nail matrix at the base of the nail

. In summary, fingernails are made of keratin, a strong protein that forms a protective plate at the tips of fingers and toes, produced continuously by the nail matrix beneath the skin