GUIDE

What is market capitalization?

The definition

Market capitalization, usually shortened to market cap, is the total market value of a company's shares. You get it by multiplying the price of one share by the number of shares that exist. If a company has two billion shares outstanding and each is priced at ten dollars, its market cap is twenty billion dollars. The result is a measure of size as the stock market currently sees it, not a measure of what the company owns or earns.

Because the price changes every trading day, market cap changes too. It also changes when the share count changes, for example when a company issues new shares, cancels some, or splits its stock. A split multiplies the number of shares and divides the price, so on its own it leaves market cap unchanged.

A worked example from today's table

In the snapshot dated 2026-10-30, the company at the top of the league is Apple Inc. (AAPL), with a derived market capitalization of $5.03T. The company in second place, NVIDIA CORP (NVDA), stands at $4.93T, which leaves a gap of $96.92B between first and second. At the other end of the table, Prologis, Inc. (PLD) is ranked 100 at $119.36B.

All 100 companies together add up to $53.82T, so the leader accounts for 9.3% of the combined total. Those are statements about size within this table. They say nothing about whether any of these businesses is doing well or badly. Compared with the snapshot dated 2026-10-19, its derived market cap rose from $5.01T to $5.03T, a difference of $25.98B (+0.52%). Whether that came from the share price, the share count or both cannot be read from the total alone. The SEC share count used for this company is dated 2026-07-17, 105 days before the snapshot date.

What market cap is not

It is not revenue. Revenue is the money a company brings in from the goods and services it provides over a period. A company can have a huge market cap and modest revenue, or the reverse. The two numbers answer different questions: one is a stock-market price tag, the other is business activity.

It is not enterprise value. Enterprise value starts from market cap and then adds debt and subtracts cash, to describe the value of the whole business to everyone who has a claim on it. Two companies with the same market cap can have very different debts, so their enterprise values can be far apart.

It is not profit or book value. Neither the earnings a company reports nor the accounting value of its assets appear in the calculation.

It is not the share price. A company with a high share price is not necessarily larger than one with a low share price. A hundred-dollar share in a company with ten million shares is far smaller than a ten-dollar share in a company with ten billion. This is why the league ranks by market cap and publishes no raw prices.

It is not a verdict. A large market cap does not mean a company is good, safe or fairly priced, and a small one does not mean the opposite. The figure is a snapshot of what the market's price implied at one close. This site does not judge whether any company is worth more or less than that.

Details that complicate the picture

Some companies have several classes of shares that trade under different tickers, so a fair total adds the classes together rather than counting one. Some foreign companies list American depositary receipts that each stand for a fixed number of underlying shares, so the ratio matters. Market cap also counts every share, including those held by founders and insiders, so it is not the same as the value of shares that are freely available to trade, which is sometimes called the float. The league's method for these cases is described in how the league is calculated.

Why rankings move

A company can climb the table because its own value rose, because those above it fell, or because the share count behind its figure was updated. A company can also fall without its own value changing at all. Reading the standings as a ranking by size at a point in time, rather than as a score for performance, avoids most misunderstandings. To see how the data behind these numbers is gathered, read data sources and schedule, or look at the latest biggest movers.

Informational only, not investment advice.