The chain

Reading a row

Each chain row carries (per side) the bid, ask, mark, IV, delta, gamma, vega, theta, OI, and 24h volume. That's seventeen numbers per row, far too many to scan unfiltered. The pro terminal's chain panel is built around filters that strip the row down to just the strikes you actually care about.

• Expiry, limit to a single expiry token (e.g. 28MAR25). Without this, you're looking at every strike across every expiry simultaneously.
• OI minimum, drop strikes with thin OI. Most of the chain is empty or near-empty; a 100-contract minimum often cuts the table by 80% without losing signal.
• Delta range, limit to OTM (e.g. 0.05–0.30 delta) or to ATM (0.40–0.60). Useful when reading skew or looking for cheap optionality.
• Strike range, limit by dollar price, e.g. within 10% of spot.
• Type, calls only or puts only.

The expiry summary

The expiry summary panel collapses the chain to one row per expiry, surfacing the headline metrics for each: DTE, ATM IV, 25Δ skew, max pain, net GEX, P/C ratio, and the OI breakdown. The front row (nearest expiry) is highlighted because that's the one driving the most short-term flow.

The summary is the fastest way to see how positioning evolves along the curve. Front expiries usually carry concentrated 0DTE flow; back-month expiries are slower and structural.

OPEX countdown

The OPEX panel shows the countdown to the next major monthly / quarterly expiry, plus notional expiring (calls, puts, total), max pain, pin risk, and the 1σ expected move from spot to expiry. It also surfaces the front-expiry vol and skew read (ATM IV, 25Δ skew, 10Δ skew, 25Δ RR, 25Δ fly, 25Δ put/call IV) and the expiring-option stats (call OI, put OI, total OI, P/C ratio). Big OPEX dates (notably the last Friday of each quarter) typically have notional in the tens-of-billions and are the most consequential gamma events on the calendar.

Put / call ratio

The put/call ratio is open interest in puts divided by open interest in calls. Above 1 = more puts than calls (defensive positioning); under 1 = more calls (offensive).

The PCR panel surfaces the ratio over time so you can read the current value against its own history. Like funding, the level isn't actionable on its own, the regime context is.

OI history

The OIHIST panel breaks open interest out by call vs put across time. Surfaces shifts in positioning that aren't visible in a single chain snapshot, e.g. call OI exploding two weeks before a major expiry signals call buying ahead of an event. See also: perp OI for the perpetual-futures sibling.