An order book is a real-time list of buy and sell orders for a financial instrument, organized by price level. It shows the supply and demand at different prices.

Structure

Bids (Buy Orders):

Price Volume
1.0850 50 lots
1.0849 30 lots
1.0848 80 lots

Asks (Sell Orders):

Price Volume
1.0851 40 lots
1.0852 60 lots
1.0853 25 lots

Reading the Order Book

  • Large bid walls — Strong support (many buyers)
  • Large ask walls — Strong resistance (many sellers)
  • Thin book — High volatility potential
  • Spread — Gap between best bid and ask

Limitations

⚠️ Not all orders are visible (hidden/iceberg orders) ⚠️ Orders can be placed and cancelled instantly (spoofing) ⚠️ More useful for crypto/stocks than forex ⚠️ Requires Level 2 data access