Explainer

What the VIX is

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By AP's Morning Brief · October 27, 2026 · Definition from Cboe · No live VIX level on this page

The Cboe Volatility Index (VIX) is a number derived from S&P 500 Index option prices. Cboe describes it as a leading measure of market expectations of near-term volatility conveyed by those options. Since its introduction in 1993, many market participants have treated it as a barometer of investor sentiment and expected volatility — sometimes nicknamed the “fear gauge.”

General information and education only. Nothing here is a recommendation to buy, sell or hold any security.

In plain words

• It is not the S&P 500 itself. It is an index built from option prices on the S&P 500.
• When option prices imply more turbulence ahead, the VIX tends to be higher; when they imply a quieter near term, it tends to be lower.
• Cboe notes a historically strong inverse relationship between the VIX and the S&P 500: sharp equity selloffs often coincide with VIX spikes. That is a tendency, not a law you can trade blindly.

What it is not

• Not a crystal ball. It reflects what option markets are pricing for near-term volatility, not a guarantee of what will happen.
• Not the same as futures or options on the VIX. Cboe also lists VIX futures and options; those are separate products with their own behaviour (including mean reversion in the futures term structure, which Cboe discusses in its VIX materials).
• When we mention it in a brief. If an edition cites a VIX level, it will link the source and the timestamp; this evergreen page keeps no live quote so the explanation doesn’t rot.

Where to read the live level

For a current reading, use Cboe’s own VIX product page or a delayed quote panel — not a number copied into this article. Cboe: https://www.cboe.com/tradable_products/vix/. Our Markets page uses TradingView widgets for indexes and macros (Data: TradingView); check whether VIX appears in your quote source before relying on it.

Sources

1. Cboe, “Cboe Volatility Index” / VIX tradable products page (definition and product overview): https://www.cboe.com/tradable_products/vix/

General information and education only.

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