The Depth of Market (DOM), also called the order book or Level 2, shows you the resting limit orders sitting at every price level above and below the current market. It is the queue of unfilled orders waiting for price to come to them. Every other tool in this curriculum shows you what happened. The DOM shows you what is sitting there right now, waiting to happen.
Bid and Ask in the order book
The bid side is the queue of limit buy orders. These are buyers who have placed orders at specific prices and are waiting for the market to come down to them. The ask side is the queue of limit sell orders: sellers waiting for the market to come up to them. Between them is the spread.
When a market order to buy executes, it matches against the lowest ask in the queue. When a market order to sell executes, it matches against the highest bid. The DOM shows you the depth of each side: how many contracts are waiting at each price level, and how far that depth extends.
| Bid | Price | Ask |
|---|---|---|
| 5248.75 | 180 | |
| 5248.50 | 245 | |
| 5248.25 | 310 | |
| 95 | 5248.00 | 102 |
| 280 | 5247.75 | |
| 445 | 5247.50 | |
| 380 | 5247.25 |
Waiting orders vs completed trades
Footprint shows completed transactions. Every row in a footprint candle represents contracts that actually traded. That data is permanent. It cannot change. Footprint is historical, even if the history is seconds old.
The DOM shows orders that have not yet executed. They may execute when price reaches them. Or they may be cancelled before then. This is the fundamental difference: the DOM is a snapshot of intent, not a record of action. Market Profile and Volume Profile are backward-looking. Footprint is present-tense. DOM is forward-looking. All three serve different roles in the same workflow.
DOM orders can be cancelled before execution. A large order sitting on the bid can disappear the moment price approaches it. This is the central limitation of all DOM-based analysis, and the basis for the spoofing tactics covered in DOM.04. Never treat DOM orders as guaranteed support or resistance.
The forward-looking layer
Used correctly, DOM adds something VP and footprint cannot: a view of where size is sitting right now. A VP HVN tells you where the market traded heavily in the past. If you see large bid stacking at that same price on the DOM today, you have two independent signals pointing at the same level. The historical profile identified it as significant. The DOM shows active participants defending it in real time.
DOM is most useful to traders in liquid futures markets (ES, NQ, ZN, CL) where the order book is deep enough to be meaningful. In thin markets or equities, the book is easier to manipulate and harder to read reliably. Platforms with DOM: Sierra Chart, Jigsaw Trading, Bookmap, NinjaTrader, ATAS. Each has different visualization options for the book.
SpeedThe DOM moves faster than you think
In liquid instruments, the order book refreshes constantly. Individual orders appear, grow, shrink, and vanish within fractions of a second. The skill is not reading individual order sizes. It is pattern recognition: is the bid building or thinning? Is the ask stacking or pulling? Is size appearing and staying, or appearing and disappearing? Developing that pattern recognition requires significant screen time. Most traders use the DOM as a secondary confirmation layer rather than a primary signal source.