Float (Public Float)

A company's float is the number of shares actually available for public trading, calculated as total shares outstanding minus shares held by insiders, large strategic holders, and other restricted or closely-held stakes. Float, not total shares outstanding, is what determines how easily a stock can be bought or sold without moving the price.

A low float relative to shares outstanding means fewer shares are actually changing hands, which can make a stock far more volatile than its market cap alone would suggest, since the same dollar amount of buying or selling pressure has a much bigger price impact when the tradable pool is small.