Central Limit Order Book (CLOB)
A CLOB is a centralized database of buy and sell orders for a specific financial instrument, organized by price level.
Matching Logic: 1. Price Priority (Best price wins). 2. Time Priority (First come, first served). Order Types: Limit (Fixed price), Market (Immediate fill), IOC (Immediate or Cancel). Benefits: Price discovery, Transparency, Tight spreads for high volume. Disadvantages: High computational cost for decentralized apps.
graph LR
Center["Central Limit Order Book (CLOB)"]:::main
Rel_caching["caching"]:::related -.-> Center
click Rel_caching "/terms/caching"
Rel_file_systems["file-systems"]:::related -.-> Center
click Rel_file_systems "/terms/file-systems"
Rel_thread["thread"]:::related -.-> Center
click Rel_thread "/terms/thread"
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🧒 Explain Like I'm 5
Imagine a big, public chalkboard at a fruit market. Everyone who wants to buy apples writes their price on the left side, and everyone who wants to sell apples writes their price on the right side. A 'Matching Engine' (the market manager) looks at the board and says: 'Hey, Bob wants to buy for $5 and Alice is selling for $5—DEAL!' That chalkboard is the CLOB.
🤓 Expert Deep Dive
Technically, a CLOB matching engine maintains two 'Priority Queues': one for bids and one for asks. The 'Spread' is the gap between the highest bid and the lowest ask. CLOB efficiency is measured by 'Liquidity Depth'—the volume available at each price level. While CLOBs are standard in centralized finance, they are difficult to implement on-chain in DeFi due to gas costs and network [latency](/en/terms/network-latency). However, high-performance blockchains like Solana (e.g., Project Serum/OpenBook) have successfully implemented on-chain CLOBs. In these environments, 'Market Makers' use complex algorithms to keep the book filled, while 'Arbitrageurs' ensure the CLOB price stays aligned with other global markets.