STX implied volatility
From the closing options book · October 20, 2026 · updated after every close
STX's at-the-money implied volatility was 82.8% at the October 20, 2026 close. Over the past 260 sessions it ranged from 49.7% to 128.8%, putting today's level at an IV rank of 42 and IV percentile of 68.
STX at-the-money IV, last 60 sessions
Options were pricing more movement than STX actually delivered over the last 20 sessions (82.8% implied against 69.6% realized).
IV rank places today's IV between the period's low (0) and high (100); IV percentile is the share of sessions with lower IV. Both use STX's own closing history.
These are the October 20, 2026 closing numbers. Members see STX's map move live all session.
Common questions
82.8% at the money at the October 20, 2026 close.
42 over the past 260 sessions (IV percentile 68).
Its IV percentile is 68: middling against its own past year.
Compare: implied volatility on other tickers
Measured from the closing options book and rebuilt after every close. Nothing on this page is live. Levels are where dealer hedging is concentrated, not targets or forecasts. Not investment advice.