Float is the number of shares actually available for the public to trade — total shares outstanding minus insider holdings, restricted shares, and locked-up stock.
Two companies can both have 100 million shares outstanding, but if insiders hold 90 million of one, only 10 million shares are really trading hands. That difference changes how the stock behaves more than almost anything else.
Price is set by supply and demand. When a catalyst hits a stock with a small float, a lot of buyers compete for very few shares. There is simply not enough supply to absorb the demand, so the price gaps and runs.
That is why the biggest one-day percentage gainers are almost always low-float names. A 5-million-share float with real news can double in hours. A 2-billion-share float needs enormous money flow to move 5%.
Low float cuts both ways. The same lack of supply that fuels the rally disappears on the way down — when buyers step away, there are few natural bids to catch the fall, and low-float runners can give back an entire move in minutes.
Low-float companies are also frequent issuers of new shares. A parabolic run is often a company's best chance to raise money, and a dilutive offering can end the party overnight.
Before chasing any big mover, experienced traders check three things together: the float, the volume, and the catalyst. A runner on high relative volume with a real catalyst and a small float is a fundamentally different setup from a large-cap drifting up on no news.
As a rough guide, traders often call floats under ~20 million shares "low float" and under ~5 million "micro float", though there is no official definition.
No. Float describes how a stock is likely to behave, not which direction it will go. Low float amplifies moves in both directions.
Most brokers and financial data sites list float under key statistics. Scanning tools like TheScanner surface float alongside volume and catalysts automatically.
Shares outstanding is every share that exists. Float is only the portion the public can actually trade — outstanding minus insider, restricted, and locked-up shares.
TheScanner watches premarket gappers, unusual volume, whale flow, insider buying, and news catalysts across the whole market — and logs every alert so the track record is verifiable. Research tool, not investment advice.
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