Today's movers with a small number of shares actually available to trade. Float is what is left after insiders, restricted stock and closely held blocks are removed. When a stock with a two million share float trades fifty million shares, the entire float has turned over many times in a day, and price moves become violent in both directions.
Float is the number of shares genuinely available for the public to trade. It is total shares outstanding minus the stock that is not going anywhere: insider holdings, founder stakes, restricted shares still inside a lockup, and large strategic positions held by parties with no intention of selling.
A company can have two hundred million shares outstanding and a float of eight million. Only those eight million set the price, because they are the only ones changing hands. This is why market capitalisation alone tells you very little about how a stock will behave intraday.
Price is set at the margin, by whoever is willing to transact right now. When the pool of available shares is small, each buy order consumes a larger proportion of the resting sell orders, so the price has to move further to find the next seller.
The practical effect is that the same dollar of buying pressure produces a much larger percentage move in a low float name than in a liquid one. A single piece of news that would lift a mega cap by one percent can move a two million share float by thirty, because there is simply nothing there to absorb the order flow.
This cuts both ways, and the downside is where people get hurt. The same thin order book that produced the move up offers nothing to lean on when it reverses. There is no bid.
A small float on its own is inert. Thousands of stocks have tiny floats and never move, because nobody is trading them. What creates the move is a small float meeting unusual volume.
Relative volume compares today's volume against the stock's own average. A low float name running at twenty times normal volume is where the dynamic described above actually plays out. The same name at average volume is simply illiquid, which is a risk without a corresponding opportunity.
Read the float column and the volume column together. Neither tells the story by itself.
Dilution. Low float companies are frequently small companies that need capital. The most common way a thin float resolves is that the company issues more stock into the strength, which is exactly what you would do if you ran the business. A float can expand overnight.
Spreads. The bid-ask spread on a thin name can be several percent wide. You pay that twice, going in and coming out, before the position has done anything at all.
Halts. Exchanges halt volatile moves. A halt locks you in place while news develops, and the reopen is frequently nowhere near the price it halted at.
Float data is an estimate. Float is derived from filings that lag, so a figure here can be out of date if the company has issued stock recently.
The table lists stocks below the float threshold you set, alongside price, volume, relative volume and market cap. The float filter is adjustable because the right threshold depends entirely on what you are looking for. Under ten million shares is genuinely thin. Under two million is extreme and comes with the liquidity problems described above.
Float figures come from a third party and are not available for every symbol. Where float cannot be determined the stock does not appear, rather than appearing with a guess.