What Is Market Cap? Market Capitalization Explained

Market cap (market capitalization) is the total dollar value the stock market assigns to a company: stock price × shares outstanding.

Market Cap Categories

Mega-cap: above $200B (Apple, Microsoft, Nvidia). Large-cap: $10B–$200B (S&P 500). Mid-cap: $2B–$10B (S&P MidCap 400). Small-cap: below $2B (Russell 2000). Micro-cap: below $300M.

Why Market Cap Matters More Than Stock Price

A stock at $5 could be a $50 billion company with 10 billion shares outstanding. A stock at $5,000 (like Berkshire Hathaway Class A) may be worth $1 trillion. Always compare companies by market cap, not share price.

Market Cap vs. Enterprise Value

Enterprise Value = Market Cap + Debt − Cash. EV gives a more complete picture of what it would cost to acquire a company, and is used in ratios like EV/EBITDA for valuation comparisons.

StocksRankings covers S&P 500 (large-cap), Nasdaq 100 (mega-cap), and S&P MidCap 400 stocks. See all rankings.