Market Capitalization
The total market value of a company's outstanding shares. Market Cap = Share Price × Shares Outstanding.
Formula
Market Cap = Share Price × Shares Outstanding
Market capitalization is the most widely used single number to size a company. It represents what the public market collectively says the entire business is worth at the current moment.
Market cap drives index inclusion, ETF weighting, and investor mandates (many funds are restricted to large-cap or small-cap). It is also the starting point for valuation comparisons between companies in the same sector.
Market cap alone does not capture debt. Enterprise value adds net debt to give a truer acquisition cost, which is why analysts often prefer EV-based multiples (EV/EBITDA) to market-cap-based ones (P/E) when comparing capital-intensive businesses.
Example
Apple has ~15.4 billion shares outstanding trading at $200. Market cap = 15.4B × $200 = $3.08 trillion. A small startup with 5 million shares at $10 each has a $50 million market cap — micro-cap territory.
Related Terms
Enterprise Value (EV)
The total cost to acquire a business outright: market cap plus net debt. The true takeover price, capital-structure-neutral.
IntermediateEquity
Ownership value in an asset after all debts are subtracted. In markets, "equity" usually means stocks.
BeginnerFloat
The number of shares freely available for public trading, excluding insider-held and restricted shares.
IntermediateIndex
A benchmark measuring the performance of a selected group of securities — the S&P 500 tracks 500 large US companies.
BeginnerIPO
The first time a private company sells shares to the public on a stock exchange, raising capital and creating a tradable market for the stock.
IntermediateLarge Cap
Companies with a market capitalization generally above $10 billion. Large caps are the most liquid, most-analyzed tier of the stock market.
BeginnerMarket-on-Close (MOC) Order
A market order that executes in the official closing auction at the day's closing price. Used to guarantee a close print; large MOC imbalances can move price into the bell.
IntermediateMid Cap
Companies with a market capitalization roughly between $2 billion and $10 billion — the "sweet spot" for growth with established business models.
BeginnerPEG Ratio
P/E ratio divided by the expected annual EPS growth rate. Adjusts valuation for growth — a PEG near 1.0 is often seen as fair value.
IntermediatePenny Stock
Stocks trading below $5 per share, often in tiny companies. Highly speculative, illiquid, and prone to manipulation.
BeginnerPrice-to-Book (P/B) Ratio
Share price divided by book value per share. Shows how much you pay per dollar of accounting net worth.
IntermediatePrice-to-Sales (P/S) Ratio
Market cap divided by annual revenue. A valuation multiple that works even when a company has no earnings.
IntermediateShares Outstanding
The total number of a company's shares currently held by all shareholders, including insiders and institutions.
BeginnerSmall Cap
Companies with a market capitalization roughly between $300 million and $2 billion. Higher growth potential but also higher risk than large caps.
IntermediateStock
A unit of ownership in a company. Buy stock and you own a slice of the business, with rights to a share of earnings and assets.
BeginnerStock Split
When a company divides each existing share into multiple new shares, lowering the price per share while total value stays the same.
Beginner