Depth of market — The order book view showing resting bids and offers at each price level around the current market.
How depth of market works in prop trading
The DOM shows how much size is resting at each price, not just the best bid and offer. Futures traders use it to place and manage orders directly on the ladder, and to judge whether the depth in front of them supports the size they intend to trade. It is the standard execution interface in futures platforms.
Read with care. Resting size is not a commitment — orders can be pulled instantly, and in fast markets the visible book empties before you can act on it. Its most reliable use for a prop trader is the plain one: confirming there is enough size at your price to fill your order without walking several levels and paying for it in slippage.
Key points
- Shows resting size at each price level, not just the top of book.
- Resting orders can be cancelled at any time, so displayed depth is not a guarantee.
- Its most dependable use is checking the book can absorb your size at your price.
- Depth thins dramatically outside US cash hours and around scheduled releases.
Also known as
- DOM
- order book
- ladder
- price ladder
Frequently asked questions
What is a DOM in futures trading?
Depth of Market — a vertical price ladder showing resting bid and ask size at each level, with order entry built into it. It is the standard execution interface on futures platforms like NinjaTrader, Tradovate, and Quantower.
Is the order book reliable?
As a snapshot of resting size, yes. As a prediction, no — orders can be cancelled instantly and often are in fast markets. Use it to check your size can fill at your price rather than to infer where the market will go.
Depth of market is described here as a plain-language educational definition. Firms, platforms, and account programs may apply different conditions or calculations. Verify the current official terms before using this definition to make an account decision.