Which major U.S. stock index is heavily weighted toward technology stocks?

The Nasdaq Composite is the major U.S. stock index heavily weighted toward technology stocks.

The index tracks almost all equity securities listed on the Nasdaq stock exchange and is capitalization-weighted, so companies with larger market values exert greater influence. Because many prominent technology and technology-related firms list on Nasdaq, information technology has historically made up a large share of the index.

The Nasdaq Composite is often confused with the Nasdaq-100. The Composite covers nearly all eligible Nasdaq-listed stocks, whereas the Nasdaq-100 follows 100 of the largest nonfinancial companies listed there. The S&P 500 is broader across industries, the Dow Jones Industrial Average contains 30 blue-chip companies, and the Russell 2000 focuses on smaller U.S. companies.

Technology’s heavy representation does not make the Composite a pure technology index. It also includes companies from sectors such as healthcare, consumer goods, financial services, and communications, provided they meet Nasdaq’s eligibility rules.