DOM ladder

The DOM ladder is a vertical price ladder: one row per price level, current price anchored in the middle, resting liquidity on both sides and the tape landing on it in real time.

Where the footprint chart is history you read across, the ladder is the present moment you read down. Both follow the primary instrument only — the aggregate set does not feed this panel, so switching the primary switches the ladder with it.

The columns

Reading outward from the price column in the centre:

Bid size and ask size — resting limit orders at each level, straight from the book. This is what is currently sitting there, and it can be pulled at any moment.

Traded volume at price — how much has actually printed at each level. Unlike resting size, this cannot be cancelled: it is a record of transactions. Preload fills this from history so the ladder is not blank when you arrive.

The mid marker tracks the current price and, by default, keeps it centred. Auto-centre is a toggle — turn it off when you want to park the view on a level and watch price come to it.

Grouping and notional

Both controls sit in the panel header.

Grouping buckets adjacent price levels into one row, the same idea as the footprint chart's tick selector. On a liquid perp the raw tick is far finer than any level anyone actually defends; grouping to something like $10 turns a wall of single ticks into readable shelves.

The $ button switches every size column between raw coin quantity and USD notional. It turns the accent colour when notional is on, and remembers its own setting independently of the other panels.

What it is good for

Absorption. A level where the resting size keeps getting hit but keeps being replenished, while price fails to move through, is being defended by someone with real size. The traded-volume column climbs, the resting-size column does not empty, and price stalls.

Pulled liquidity. A large resting level that disappears without any traded volume against it was never a real bid. Watching size vanish ahead of price is one of the clearest tells the ladder gives you.

Where size is being worked. A participant filling a large order leaves a signature: steady traded volume at a narrow band of levels over minutes, without the resting size ever looking dramatic.

Pairing it with the composite book

The ladder is single-venue by design — that is what makes it a faithful picture of the book you would actually hit.

For the cross-venue view, keep the Orderbook panel open beside it. That panel draws one column per aggregate member, so you get the composite picture there and the exact book here. The two answer different questions and it is worth having both on screen.