What Is the VIX?

The VIX — formally the CBOE Volatility Index — measures the market's expectation of 30-day volatility on the S&P 500. It's calculated from the prices of SPX options across multiple strikes. When traders pay more for SPX puts and calls, the VIX rises. When those premiums fall, the VIX drops.

The VIX is quoted in annualized percentage terms. A VIX of 20 means the market expects the S&P 500 to move about 20% over the next year, or roughly 1.26% per day (20 ÷ √252).

VIX Levels and What They Mean

| VIX Level | Market Regime | What It Signals | Below 13Extreme complacencyVery cheap premiums, low fear 13-17Low volatilityNormal bull market conditions 17-22ModerateTypical range, balanced sentiment 22-30ElevatedIncreased fear, corrections possible 30-40High fearBear market territory, panic selling | Above 40 | Crisis | Extreme panic (2008, 2020 March) |

The long-term VIX average sits around 19-20. Spend time trading and you'll develop intuition for these ranges.

Converting VIX to Expected Daily Moves

The VIX gives you a direct way to estimate how much SPY might move on any given day:

Daily expected move = SPY price × (VIX / 100) / √252

If SPY is at $540 and VIX is at 18:

  • Daily expected move = $540 × 0.18 / 15.87 = $6.12

    • This means the options market expects SPY to move about $6 per day, or about 1.13%. Moves beyond this are "larger than expected" and often trigger further volatility.

    How to Use VIX in Your Trading Decisions

    When VIX is low (below 15):

  • Option premiums are cheap across the board
  • Premium selling generates less income per trade
  • Consider buying strategies (debit spreads, LEAPS calls)
  • Widen your iron condor wings — you need more room when complacency reverses
  • Hedge existing portfolios cheaply with protective puts

    • When VIX is moderate (15-22):

  • Normal conditions for most strategies
  • Premium selling works well at standard position sizes
  • No special adjustments needed

    • When VIX is elevated (22-30):

  • Premiums are rich — excellent for sellers
  • Increase the width of credit spreads to account for larger moves
  • Reduce position size per trade (bigger moves mean bigger swings)
  • Avoid selling naked options unless you're experienced
  • Good environment for iron condors if you can handle the whipsaw

    • When VIX is high (above 30):

  • Extreme premiums available for sellers
  • But realized moves are also extreme — tread carefully
  • Use defined-risk strategies exclusively (spreads, not naked positions)
  • Consider selling put spreads on quality stocks that are oversold
  • Size positions at 50-75% of normal to survive potential spikes to 40+

    • VIX Mean Reversion: The Key Insight

    The VIX has a powerful tendency to revert to its mean. Spikes above 30 historically resolve within 2-6 weeks. Periods below 13 typically don't last more than a few months before a correction bumps volatility higher.

    This mean-reverting behavior creates a structural edge for volatility traders. When VIX is elevated:

  • Selling premium benefits from both the high starting IV and the subsequent decline
  • Calendar spreads benefit from the front-month IV dropping faster than back-month
  • Volatility ETFs like UVXY tend to bleed value as VIX normalizes

    • Common VIX Mistakes

    Mistake 1: Thinking VIX predicts direction. VIX measures expected magnitude, not whether the market goes up or down. A falling VIX often accompanies rising markets, but that's a correlation, not a rule.

    Mistake 2: Buying VIX ETFs as hedges. Products like VXX and UVXY lose value over time due to contango in VIX futures. They work for short-term hedges (days), but holding them for weeks or months guarantees losses.

    Mistake 3: Ignoring VIX when trading individual stocks. Even if you're trading AAPL options, macro volatility affects everything. A VIX spike from 15 to 30 will inflate premiums across most stocks.

    Use OptionsPilot to track how changes in market volatility affect the premium available on specific stocks you're watching.