Ask size shows the quantity available at the current best ask price and, on some platforms, the sizes at additional ask levels shown in the order book. It is part of market data that reflects the depth of the ask side.
Traders compare the ask size with the corresponding bid size to gauge immediate liquidity and potential price response to new orders. A larger size at the best ask suggests more immediate supply at that price, while a smaller size may indicate thinner liquidity at the top of the ask. The measure is often considered together with the bid-ask spread and overall market depth to understand how easily price may move when new orders arrive.
Ask size is a snapshot that can change quickly as orders are added, canceled, or executed. Some venues show additional or hidden liquidity not captured in visible sizes, which can influence execution risk. In context, ask size helps readers of quotes form a sense of market microstructure and liquidity conditions.
For example, in a streaming quote, the best ask shows 40,000 shares at $29.50, indicating there are 40,000 units available at that price.
Ask price · Bid size · Bid-ask spread · Order book · Market depth · Liquidity