Interactive Order Book

Simulated AAPL order book. Send market orders to see how matching works in real time.

$150.03
Ask $150.04 Bid $150.02 Spread $0.02
Ask (sell-side)Qty
Bid (buy-side)Qty
Waiting for action…

Market Order

Executes immediately at the best available price. The active side — it accepts the passive side's price.

Limit Order

Sits in the order book at a specified price. The passive side — it creates liquidity and sets the price.

Bid–Ask Spread

The gap between the best ask and best bid. Narrower spreads mean a more liquid, competitive market.

Last Price

The price of the most recent completed trade. This is the big number shown on platforms like Robinhood.

Marketable Limit Order

A limit order priced to cross the spread — bid ≥ best ask, or ask ≤ best bid. Matches immediately like a market order, consuming queued orders until price is no longer satisfied.