VIX to Daily Move Calculator

Annualised implied volatility and a daily trading range are the same quantity on two clocks. Because volatility scales with the square root of time and a year holds about 252 trading days, dividing an annualised figure by the square root of 252, which is 15.87, converts it to a one-day standard deviation. Traders round that to 16 and call it the rule of 16.

This converter does the arithmetic and draws what it means: enter a VIX level and it returns the implied one-day move in percent, alongside the distribution of daily outcomes that level implies. A VIX of 16 prices roughly one percent moves as the one-standard-deviation day; 32 prices two percent; a VIX of 80, the kind of print seen in genuine crises, prices five percent swings as normal.

The number is a market-implied expectation, not a forecast. Roughly one day in three should close outside the one-sigma band if the pricing is fair, which is exactly what makes the comparison between implied and subsequently realised moves informative.

Background reading: VIX in the Knowledge Hub · All tools