Depth of market (DOM) data looks intimidating the first time you open it — a scrolling grid of prices and sizes that updates faster than you can read it. Once you know what each column represents and what it can't tell you, it stops being noise and becomes one more useful input.
What You're Actually Looking At
The order book shows resting limit orders on both sides of the current price — bids below, offers above — along with the size at each level. It's a snapshot of stated intent to buy or sell at specific prices, not a guarantee that those orders will execute, or even that they'll still be there by the time you look again.
What It Can (and Can't) Tell You
A large resting order at a specific level suggests some participant is comfortable buying or selling there — worth noting as a potential area of interest. It does not mean price won't blow through that level, and large orders can be pulled the instant price approaches them, a practice sometimes called "spoofing" that regulators actively police but can't fully eliminate. Treat visible size as informative, not predictive.
- Order book depth thins out fast around news events — don't expect the same liquidity you see in quiet conditions
- Large resting orders can disappear before price reaches them; don't treat them as guaranteed support or resistance
- DOM is more useful for very short-term execution decisions than for building a directional thesis
- Combine it with price action context — depth of market in isolation, without a read on trend or momentum, is easy to misread
Like most tools, the order book rewards traders who use it to refine an existing plan rather than to generate one from scratch. Start by simply watching it alongside price for a session or two before trying to trade off it directly.
