Glossary
Market Cap
Market capitalization is the total market value of a company's outstanding shares. It is the most common way to size a publicly traded company and bucket it as small-, mid-, or large-cap.
Market capitalization (or market cap) is the total dollar value of a company's outstanding shares of stock. It is calculated as:
Market Cap = Current Share Price × Total Shares Outstanding
A company trading at $150 with 10 billion shares outstanding has a market cap of $1.5 trillion.
Why market cap matters
- Size proxy: AAPL at $3T behaves very differently than a $300M small-cap biotech. Market cap tiers group companies by risk and growth profile.
- Index inclusion: S&P 500, Russell 2000, MSCI World — all use market-cap thresholds to decide which stocks to include.
- Acquisition math: in a cash deal, market cap (plus a control premium) is roughly the price an acquirer has to pay.
The standard buckets
| Tier | Range | Profile |
|---|---|---|
| Mega-cap | > $200 B | Apple, Microsoft, Saudi Aramco, NVIDIA |
| Large-cap | $10 B – $200 B | Established, global, often dividend-paying |
| Mid-cap | $2 B – $10 B | Growth-stage with proven product-market fit |
| Small-cap | $300 M – $2 B | Higher volatility, less analyst coverage |
| Micro-cap | < $300 M | Speculative, low liquidity, often OTC |
Free-float vs. total market cap
Not all shares are publicly traded. Insiders, founders, and governments often hold large blocks. Free-float market cap excludes those locked-up shares and is a more accurate measure of the investable opportunity.
Enterprise value (EV) vs. market cap
Market cap ignores debt and cash. Enterprise Value = Market Cap + Total Debt − Cash & Equivalents. EV is the correct denominator for ratios like EV/Sales and EV/EBITDA because it reflects the actual cost to acquire the whole business.
Limitations
- Float manipulation: buybacks reduce share count and inflate per-share metrics without changing fundamentals.
- Crypto is different: "market cap" of a coin = price × circulating supply. Be wary of "fully diluted" numbers that include locked or pre-mined tokens.
- Pre-revenue companies: market cap is purely speculative when earnings are zero or negative.
See also
- P/E Ratio — earnings-based valuation.
- Forecast estimates — target-date model estimates.
- Stock directory — browse covered stocks and market estimates.