Historical Volatility
Volatility & Bandsdraws in its own pane
What the stock actually did, in the same units as IV. The premium seller's other half — IV rich against HV is the edge being paid for.
On this chart: 20-day, annualized % from log returns.
What it measures
Historical (realized) volatility annualizes the standard deviation of the last 20 daily log returns — expressing what the stock actually did in exactly the units implied volatility uses for what the options market expects. A stock moving about 1% a day runs roughly 16% HV; the annualization constant (√252) is why.
How to read it
Level and direction both matter: HV at 30% and falling is a storm passing; at 30% and rising, one arriving. Because the 20-day window drops old days as it rolls, a single wild session inflates HV for exactly a month and then falls out — a cliff in the pane that marks the anniversary of the event, not new quiet.
Using it on the wheel
Premium selling is, mechanically, selling implied volatility — and this pane is the realized side of that trade. IV sitting well above HV describes options priced for more movement than the stock is delivering, the gap the wheel harvests. IV at or below HV describes premium that undercompensates demonstrated movement. The screener's IV metrics answer this at the chain level; the pane shows the stock's half of the comparison over time.
Like everything in this guide, these are descriptions of conditions and reference levels — context for your own decisions, not instructions to trade.