What is the S&P 500 VIX Index?

The VIX Index – or Volatility Index measures how volatile the S&P 500 Index is. It judges the expectations of the stock market over the following 30-day period.

Where have you heard about the S&P 500 VIX Index?

You might have heard it being referred to as the 'fear index' or 'fear gauge'. A high VIX reading suggests that the stock market will be moving sharply either up or down within the time period.

What you need to know about the S&P 500 VIX Index.

The VIX index measures swings in the market both ways using percentage points. If investors see a high VIX, and predict that means an upside swing, they would be less willing to sell upside call stock options. But, some critics suggest the VIX predictions are not any more accurate than looking at past stock market trends. The VIX is calculated by the Chicago Board Options Exchange.