Order matching is the process of finding compatible buy and sell orders on a trading platform. On a centralized exchange, this process is normally performed by a matching engine.

Orders are organized in an order book according to price and execution priority. Buyers submit bids, while sellers submit asks. When compatible conditions exist, the system creates a trade.

Execution priority

A common model prioritizes price first and time second. More competitive prices receive priority, while orders at the same price are commonly processed according to their placement time. Exact matching rules depend on the exchange.