In the interbank forex market, bid-ask spreads can vary depending on the liquidity of the currency pair. Major currency pairs such as EUR/USD and USD/JPY have lower bid-ask spreads compared to exotic currency pairs, which have lower trading volumes and liquidity. The bid-ask spread can also widen during periods of high volatility or market uncertainty, as market makers adjust their prices to reflect the changing market conditions.

Market depth is another important concept in the interbank market. It refers to the number of buy and sell orders at different price levels, and it indicates the level of liquidity in the market. A deep market has many buy and sell orders at different price levels, indicating a high level of trading activity and liquidity. A shallow market has few buy and sell orders, indicating low trading activity and liquidity.

In the interbank forex market, market depth can be visualized using a depth of market (DOM) tool, which displays the bid and ask prices and the number of orders at each price level. Traders can use the DOM tool to gauge the level of liquidity and market sentiment, and to identify key support and resistance levels.

In summary, understanding bid-ask spreads and market depth is important for forex traders who wish to trade in the interbank market. By monitoring the bid-ask spreads and market depth, traders can gauge the level of liquidity and market sentiment, and make more informed trading decisions.