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Float and short interest, explained simply

By Omri Ben David, founder of PREZLO · September 13, 2026

Every PREZLO alert card shows three numbers under the price: market cap, float and short %. Market cap is the easy one, the total value of the company. The other two describe how a stock's shares trade. Here is what they mean and how we read them.

Float: the shares that actually trade

A company has a total number of shares. Some of them are locked up: held by founders, insiders, or big long-term holders who are not selling today. The rest, the shares that are free to change hands on the market, are the float.

Example. A company has 40 million shares. Insiders hold 30 million. The float is 10 million. Only those 10 million are out there to be bought and sold on a normal day.

Why it matters: price is set by the shares that are trading, not the shares that exist. When new buyers arrive for a stock with a float of 3 million shares, there are very few sellers to meet them, and the price can change quickly. The same is true on the way down. A small float is a small door with a crowd on both sides of it.

Small float (a few million shares): prices can change quickly in both directions, with wider gaps between one trade and the next.
Large float (hundreds of millions): it takes enormous volume to move the price. These are rarely the stocks PREZLO alerts on.

Short interest: the shares already bet against it

Selling a stock short means borrowing shares, selling them, and hoping to buy them back cheaper later. Short interest is how many shares have been sold short and not yet bought back. On the card we show it as a percentage of the float.

Example. Float 3.5 million shares, short % 4.9. About 170,000 shares are currently borrowed and sold short. If short % were 30, it would be over a million shares that someone, at some point, has to buy back.

Why it matters: short sellers have to buy their shares back at some point. When a heavily shorted stock rises, some of them may buy back to limit their losses, which adds to the buying. That is called a short squeeze. A high short % does not mean a squeeze will happen.

Reading the two together

Small float, low short %: the price depends on buyers and sellers alone. It can change quickly, and reverse just as quickly.
Small float, high short %: the most volatile combination, in both directions.
Large float, any short %: slower, steadier, harder to move.

None of this tells you where the price goes next. It describes how the stock's shares trade. We show these numbers on every alert so that you decide with them in front of you.

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This page is educational. It is not investment advice and not a recommendation to buy or sell any security. PREZLO is not a registered investment adviser. Trading involves risk, including loss of principal. Past market activity does not indicate future results.

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