Investing · 6 min read
Nifty 50 and Sensex explained, and why they matter to you
What the two numbers on every news bulletin actually measure, why they differ, and the only practical thing a normal investor should do about them.
Krish Dalal
Founder and editor, PaisaExpert. Master's in Business Management, London. · Last updated 2026-08-13
An index is a shortlist with a scoreboard. Rather than tracking thousands of listed companies, the index picks a representative set and turns their combined value into a single number. When the news says the market fell 300 points, it means that number moved, not that every company fell.
How the two differ
| Nifty 50 | Sensex | |
|---|---|---|
| Exchange | NSE | BSE |
| Companies | 50 | 30 |
| Weighting | Free-float market cap | Free-float market cap |
| Review | Twice a year | Twice a year |
| Everyday use | Most funds and derivatives track it | Most quoted in general news |
Free-float weighting is the detail worth understanding. It means a company's influence depends on the value of shares actually available to trade, not its total size. A handful of the biggest companies therefore drive most of the movement, and the index can rise on a day when the majority of listed companies fall.
Broader indices worth knowing
- Nifty Next 50, the fifty companies queued behind the top fifty. More volatile, historically higher return over long periods, and a common second holding.
- Nifty 500, roughly the whole investable market in one index. The simplest single choice for someone who wants one fund and nothing else.
- Nifty Midcap 150 and Smallcap 250, which are considerably more volatile and are best treated as a small satellite rather than a core.
Frequently asked
What to do next
- Treat the daily index number as news, not as an instruction.
- If you want one holding, a Nifty 50 or Nifty 500 index fund covers the market.
- Start a SIP rather than trying to time the entry.