The ticker symbol for the CBOE Volatility Index is VIX.
The VIX measures the stock market’s expectation of volatility over the next 30 days, using prices of S&P 500 index options. Because option prices often rise when investors seek protection from falling markets, the VIX is widely nicknamed the “fear gauge” or “fear index,” though it measures expected volatility rather than market direction itself.
The Chicago Board Options Exchange introduced real-time reporting of an original volatility index in 1993. That first version was based on S&P 100 options and is now known as the VXO. In 2003, the CBOE introduced the modern VIX methodology, using S&P 500 options and a broader range of strikes.
The VIX is an index, so investors do not buy shares of it directly. Instead, futures, options, exchange-traded products and other derivatives provide market exposure related to its movements. Similar symbols can refer to volatility measures for other indexes, such as the VXN for the Nasdaq-100 and the VXD for the Dow Jones Industrial Average.