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Nasdaq Composite profile

The Nasdaq Composite is less a selection than a census of one stock exchange. This profile explains its rules from Nasdaq's own methodology and fact sheet.

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At a glance

Provider
Nasdaq, Inc.[1]
Launched
February 1971[2]
Base value
100[3]
Constituents
Not fixed: every eligible security (3,374 as of June 30, 2026)[2]
Weighting
Market capitalization, using total shares outstanding[1]
Rebalancing
Daily; eligible securities added and ineligible ones removed each day[1]
Region / currency
No country criterion (U.S. and international companies); quoted in USD[3]

Index levels and returns change every trading day and are not shown here. Check the provider's own page for current figures.

Quick answer

The Nasdaq Composite tracks almost all common-type stocks listed exclusively on the Nasdaq Stock Market, from U.S. and non-U.S. companies alike. It is weighted by market capitalization, has no size or liquidity screen, and is rebalanced daily [1].

Key points

  • The Composite covers a whole exchange, not a hand-picked list: if a stock qualifies, it is in.
  • There is no market-cap or liquidity requirement, so very small companies are included alongside giants.
  • Weights follow market value based on total shares outstanding, so the biggest companies dominate.
  • Additions, deletions and share updates happen daily rather than on a quarterly calendar.
  • It is a different index from the Nasdaq-100, which holds only a subset of large Nasdaq companies.

#What does the Nasdaq Composite measure?

Nasdaq's methodology says the index "includes all domestic and international common type stocks listed on the Nasdaq Stock Market" [1]. In other words, it is a measure of one exchange. A stock exchange is a marketplace where shares are listed and traded; Nasdaq is one of the main U.S. exchanges. For background on how exchanges match orders, read how the stock market works.

Nasdaq's product page says the index spans all 11 industry groups of the Industry Classification Benchmark, although technology carries a large share of the weight [4]. That mix is a result of which companies choose to list on Nasdaq, not a target the index sets.

#Which securities qualify?

The rules are short. A security must be listed exclusively on the Nasdaq Stock Market and must have traded there for at least one day [1]. The methodology states there is no market capitalization criterion, no liquidity criterion and no geographic or country criterion [1].

Security types in and out of the Nasdaq Composite [1]
EligibleNot eligible
Common stocks and ordinary sharesExchange-traded funds (ETFs)
American Depositary Receipts (ADRs)Closed-end funds
Limited partnership interestsPreferred stocks and convertible debentures
Shares or units of beneficial interestRights, warrants, units and other derivatives

An American Depositary Receipt (ADR) is a certificate traded in the U.S. that represents shares of a foreign company. Including ADRs is one reason the Composite contains non-U.S. businesses. Excluding ETFs and closed-end funds avoids counting the same companies twice, since those funds hold other stocks; see what an ETF is.

#How is the Composite weighted?

The methodology calls it "a market capitalization-weighted index" whose weights come from each security's price and its Total Shares Outstanding (TSO) [1]. Market capitalization is price times shares (see market capitalization). Using total shares, rather than only the shares freely available to the public, is a design choice worth noticing. The S&P 500, by contrast, adjusts each company for float [5].

Worked example

Worked example: total shares vs float-adjusted weights

Two hypothetical companies. X: $50 share price, 600 million shares, of which founders hold 40%. Y: $30 share price, 800 million shares, all publicly traded. A third company, Z ($20, 300 million shares), lists the next day.

X market value ($50 × 600m)
$30 billion
Y market value ($30 × 800m)
$24 billion
Weights using total shares (X / Y)
55.56% / 44.44%
Weights if X were float-adjusted to 60% (X / Y)
42.86% / 57.14%
After Z joins, total-share weights (X / Y / Z)
50.00% / 40.00% / 10.00%

The weighting method decides which company leads. When a new stock joins, everyone else's weight shrinks a little.

Hypothetical companies, calculated in Python. Real Composite weights change every day.

#How often does the Nasdaq Composite change?

Every trading day. The methodology says eligible securities are added daily, securities that are no longer eligible are removed daily, and index shares are updated each day to reflect current total shares outstanding [1]. Nasdaq's product page adds that new listings join the day after they appear on the exchange [4]. That is why the number of members is never fixed.

A stock's path into the Composite

01Company listsonly on Nasdaq02Security typeis eligible03Trades for atleast one day04Added at thedaily rebalance05Removed if itdelists orbecomesineligible01Company lists only on Nasdaq02Security type is eligible03Trades for at least one day04Added at the daily rebalance05Removed if it delists orbecomes ineligible
No committee vote and no size test: the Composite follows the listing rules mechanically.

#Is the Nasdaq Composite the same as the Nasdaq-100?

No. The Nasdaq-100 is a separate index limited to large Nasdaq-listed companies. Nasdaq's product page notes that the Composite also includes financials and real estate companies not covered by the Nasdaq-100, plus thousands of smaller firms [4]. News reports often say "the Nasdaq" without saying which one, so check the name before comparing figures.

Common beginner mistakes

  1. Mixing up the Composite and the Nasdaq-100

    They hold different numbers of companies under different rules. A headline about "the Nasdaq" may mean either one.

  2. Calling it a technology index

    Technology is heavily represented, but the Composite covers every industry group. Its sector mix reflects who lists on Nasdaq, which can change.

  3. Assuming it covers all U.S. stocks

    Companies listed on the New York Stock Exchange are outside it, and many Nasdaq members are not U.S. companies. It is an exchange measure, not a country measure.

  4. Expecting thousands of stocks to mean even spread

    Because weights follow market value, a small group of very large companies can drive most of the movement. See diversification explained.

What's the bottom line?

The Nasdaq Composite is a broad, rules-light, cap-weighted measure of nearly everything listed only on Nasdaq, updated every day. It is useful for seeing how that exchange's companies move as a group, but it is not the same as the Nasdaq-100 or the U.S. market as a whole. Compare it with the committee-run S&P 500 to see how much design choices matter.

Frequently asked questions

How many stocks are in the Nasdaq Composite?

The number changes daily. Nasdaq's fact sheet listed 3,374 constituents as of June 30, 2026, but stocks join and leave as companies list, delist or change eligibility.

Are foreign companies in the Nasdaq Composite?

Yes. The methodology has no country criterion, so non-U.S. companies listed exclusively on Nasdaq, including through ADRs, can be members.

Is the Nasdaq Composite float-adjusted?

According to its methodology, weights are derived from price and total shares outstanding, updated daily. That differs from indexes such as the S&P 500, which adjust for float.

Can I invest in the Nasdaq Composite directly?

No index can be bought directly. Funds that track an index hold its stocks or a sample of them and charge fees, so their results can differ from the index.

Sources

Grade A = primary source (regulator, government agency, official rulebook or the index provider's own documents). Numbers in brackets in the text point here.

  1. Nasdaq, Inc.. Nasdaq Composite Index Methodology (2025). Accessed 2026-10-03.A
  2. Nasdaq, Inc.. Nasdaq Composite fact sheet (data as of June 30, 2026) (2026). Accessed 2026-10-03.A
  3. Nasdaq Global Indexes. Nasdaq Composite (COMP) index overview (2026). Accessed 2026-10-03.A
  4. Nasdaq, Inc.. Nasdaq Composite Index: Companies and Methodology (2026). Accessed 2026-10-03.A
  5. S&P Dow Jones Indices. Index Mathematics Methodology (September 2026) (2026). Accessed 2026-10-03.A

This page is general education, not personal financial, tax or legal advice. Figures in worked examples are hypothetical and calculated before taxes and fees unless stated. Rules and limits change; check the linked primary sources for the current version. How we check every page.