Sensex vs Nifty: What's the Difference and Why It Matters

"The market is up today" almost always means Sensex and Nifty are both up — but what are these two numbers actually measuring? You can check both, live, on our homepage.

What Sensex is

Sensex (Sensitive Index) is the benchmark index of the Bombay Stock Exchange (BSE), India's oldest stock exchange. It tracks the performance of 30 large, well-established companies across major sectors, chosen to represent the broader Indian economy.

What Nifty is

Nifty 50 is the benchmark index of the National Stock Exchange (NSE). It tracks 50 large companies — a slightly broader slice of the market than Sensex, though there's heavy overlap since both indices draw from India's largest listed companies.

Why they almost always move together

Because both indices are dominated by many of the same large-cap companies (think major banks, IT services firms, and energy companies), a significant move in any of these heavyweight stocks tends to shift both indices in the same direction, even though the exact percentage move can differ slightly due to different constituent weightings.

How the index number itself is calculated

Both use "free-float market capitalization" weighting — meaning a company's influence on the index is based on the value of its shares that are actually available for public trading (excluding promoter holdings, government stakes, etc.), not its total market value. Larger, more liquid companies move the index more than smaller ones.

Does it matter which one you follow?

For a retail investor, not particularly — both are reasonable proxies for "how is the Indian large-cap market doing today." Many index mutual funds and ETFs are built to track one or the other, so the index becomes more relevant once you're comparing specific fund options rather than just reading the news.

For the official list of current index constituents and methodology, see BSE India and NSE India directly.