Why Volume Matters
Volume is the heartbeat of the options market. Fast pulse means something's happening. Flat pulse means nobody cares — yet.
Volume shows which price levels traders are actually interested in — not just theoretically, but with real money. High volume around a strike or price level signals genuine conviction, while thin volume suggests speculative noise. For options traders, volume is one of the first filters for separating meaningful activity from background chatter.
Volume also reflects liquidity. Strikes with high volume are easier to enter and exit — tighter spreads, faster fills. Strikes with low volume carry hidden costs: wide bid-ask spreads and slippage that erode edge before a trade even begins. Always check volume before sizing into an options position.
Volume resets to zero every morning. Open Interest does not. Volume tells you what's happening today. Open Interest tells you what has accumulated over time. Used together, they reveal whether today's activity represents new conviction or just position management.
Volume vs. Open Interest
When volume at a strike significantly exceeds its open interest, it usually means fresh positions are being opened — not old ones being rolled or closed. This distinction matters: a strike with 10,000 volume but only 2,000 open interest suggests that 8,000 contracts changed hands as new bets, not as housekeeping. That's the signal worth acting on.
Conversely, when volume is high but open interest barely changes, it indicates day-trading activity — positions opened and closed within the session. These moves can still indicate where traders see value, but they don't represent durable positioning the way rising open interest does.
Unusual Options Activity
When volume at a single strike is 5–10× its typical daily average, experienced traders call this "unusual options activity" — and pay close attention. While it doesn't guarantee an informed trade, statistically outsized volume at specific strikes before earnings, FDA decisions, or macro events has historically preceded significant directional moves. It is not a signal to blindly follow, but it is a signal worth investigating.