Depth
What It Shows
The Depth view shows the total size of the options order book over time — the aggregate quantity of contracts resting in the market across all strikes and expirations for the selected ticker. Depth is a measure of market liquidity and participation.
A thick, deep book means the market is well-supplied with two-sided liquidity. A thin book means participants have pulled quotes and the market is more fragile.
Reading the Chart
The y-axis shows total order book depth (in contracts). The x-axis is time. The line tracks how depth has evolved through the session.
What changes in depth can signal:
- Depth rising — Liquidity improving; market makers are posting larger quotes. Often occurs when volatility settles and dealers are comfortable providing more size.
- Depth falling — Liquidity withdrawing. Can precede or accompany sharp moves as dealers reduce exposure. A sustained drop in depth with rising vol is a warning sign.
- Sudden depth collapse — Dealers pulling quotes rapidly, often in response to an order flow event or incoming news.
Spot Overlay
The Depth view includes an overlay of the underlying spot price on a secondary axis. This lets you directly compare order book depth to underlying price action — for example, seeing whether depth collapses precisely when spot breaks a level.
Depth Curvature
The Depth Curvature toggle adds a secondary line showing the curvature of the depth profile. This reflects how evenly distributed the liquidity is across strikes — whether the book is concentrated near ATM or spread across the surface.
Note
Depth reflects the total resting size in the order book and is not a direct measure of directional flow. A deep book does not imply buying or selling pressure — only that quotes are posted.
GEX Overlay
The GEX toggle adds a Gamma Exposure overlay, showing the estimated net gamma positioning of market makers across the surface. Positive GEX indicates dealers are net long gamma; negative GEX indicates net short gamma.
Dealers who are short gamma must buy into rallies and sell into declines to stay delta-neutral — which can amplify underlying moves. Dealers who are long gamma do the opposite, providing a natural dampening effect on price action.