Market capitalisation, usually shortened to market cap, is one of the first numbers you see on any stock or crypto page. It is a simple way to describe how large something is, and it explains a lot about how that asset tends to behave.
For a stock, market cap is the share price multiplied by the number of shares outstanding. A company with 100 million shares priced at $3 has a market cap of $300 million. For cryptocurrency, it is the price multiplied by the circulating supply, the number of coins currently available to trade. The two calculations are parallel, though crypto supply figures can be less reliable because projects count coins in different ways.
For U.S. stocks, large caps are commonly defined as above $10 billion, mid caps as roughly $2 billion to $10 billion, small caps from about $300 million to $2 billion, and micro caps below that. Boundaries vary by source, but the idea is the same: bigger companies are generally more established, more closely followed, and easier to trade.
A common mistake is to treat a low share price as meaning a small or cheap company. A $3 stock with a billion shares outstanding is worth $3 billion, while a $300 stock with a million shares is worth $300 million. Only market cap lets you compare companies of different share counts fairly. The same is true of coins: a coin priced at a fraction of a cent can be very large if billions of units exist.
Larger assets usually trade more actively, so prices move less on any individual order. Smaller ones can be pushed around by modest buying or selling. This is the main reason that smaller market caps tend to appear on top-mover lists, and also on the lists of biggest drops.
For crypto, UpTicker begins with the top 500 coins by market cap and then picks those priced under $5 with the strongest recent gains. Starting from the top 500 filters out the very smallest and least traded tokens, which are the most prone to extreme or manipulated price moves, though it does not remove risk entirely.
Market cap says nothing about whether an asset is good value. It also treats all shares or coins as if they could be sold at the current price, which is not true for large holders. It is best used as a quick check on scale rather than a judgment of quality.