Why do fingernails grow?
Short answer
The nail matrix at the base of the nail makes new cells, and those cells push the nail forward toward the fingertip.
How it works
The visible hard part of a nail is made mostly of a protein called keratin. Cells made in the nail matrix become part of the hard nail plate. As newer cells form behind them, the older parts move forward.
Fingernails grow about 3 millimeters per month on average, while toenails grow more slowly. Growth rate can vary with age, health, and injury.
Key point
Cutting the tip does not stop nail growth because the nail matrix remains at the base. The new nail is made there, rather than at the visible tip.