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Finance

What is A stock index?

A stock index measures the performance of a group of stocks, giving a quick snapshot of how a market or sector is doing. Famous examples include the S&P 500 and the Nifty 50 — when people say 'the market is up', they usually mean an index rose.

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Key things to understand

  • 1It tracks a basket of stocks as a single number.
  • 2It shows how a market or sector is performing.
  • 3Examples: S&P 500, Nifty 50, FTSE 100.
  • 4Index funds and ETFs let you invest in a whole index.

Frequently asked questions

What is a stock index?
A measure of the combined performance of a group of stocks, used to gauge a market or sector.
What are examples of stock indexes?
The S&P 500, Dow Jones, Nasdaq, India's Nifty 50, and the UK's FTSE 100.
How do you invest in an index?
Through index funds or ETFs that hold the same stocks as the index, tracking its performance.

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