Market Depth (Order Book)
The five buyers and five sellers waiting in line — and what their sizes hint at.
The market depthThe live list of buy and sell orders for a stock. window (often the “5×5” or “20×20”) shows the top pending buy orders (bids) and sell orders (asks) with their prices and quantities. It’s a live snapshot of supply and demand right around the current price.
The best bid and best ask sit at the top; the gapA jump between one bar’s close and the next bar’s open. between them is the spreadThe gap between the highest buy price and lowest sell price.. Big quantities stacked on the buy side hint at supportPrice zones where buying (support) or selling (resistance) tends to dominate.; big sizes on the sell side hint at resistancePrice zones where buying (support) or selling (resistance) tends to dominate. — pressure waiting to be absorbed.
Do I need to watch market depth as a long-term investor?
Not really. For occasional investing in liquid stocks, a limit order at a sensible price is enough. Market depth mainly helps active/intraday traders gauge immediate liquidity and likely short-term pressure.