What is a depth chart?
The depth chart is a visual way of displaying the existing buys and sells placed around the current price. It is similar to the order book in that it is constantly updating and shows the cumulative value of orders for a trading instrument/asset at given price intervals. Like with the order book, all orders shown in the depth chart are limit orders.
Components of the chart
The chart consists of the X-Axis, which shows price and the Y-Axis that shows the number of contracts for a given price in order (USD value). The very middle of the chart shows the current last price for the instrument.
Reading the chart
Reading and interpreting the depth chart can be done by hovering your mouse over the chart. Doing so will show you the number of contracts in order between the current price (the middle of the chart) and the price you are hovering over. Doing so will show you the “depth” of orders for that specific instrument. The chart will also show you how far away from price the orders you are hovering over are (in percentage terms). In the example below, orders are a maximum of 0.1% above and below the current price.