What Is Volatility Smile?
The volatility smile is a pattern observed when plotting implied volatility (IV) against strike prices for options with the same expiration. Instead of being flat (as Black-Scholes assumes), IV forms a U-shaped curve — higher for deep OTM puts and deep OTM calls, lowest for ATM options. In crypto, the pattern is often a "volatility smirk" with puts priced at higher IV than calls.
How Volatility Smile Works
The smile exists because the market prices in fat-tailed risk — the probability of extreme moves is higher than a normal distribution assumes. OTM puts command higher IV because the demand for downside protection is strong (crash insurance). OTM calls can also have elevated IV during speculative periods when traders price in the possibility of parabolic rallies.
Why It Matters for Traders
The shape and steepness of the volatility smile (or skew) provides information about market sentiment. A steep put skew (much higher IV for puts than calls) signals fear and demand for protection. A flat or inverted skew signals complacency. Changes in the skew over time reveal shifts in institutional positioning and risk appetite before they appear in the spot price.
