What the volume profile is and how it is built

The volume profile is a chart that distributes the traded volume across price levels over a range you choose, rather than over time. The result is a series of horizontal bars beside the price axis, the length of each bar measuring how much was traded at that level.

How is it built?

The price range is divided into fine slices, then the volume that occurred within each slice is summed. Where price spent a long time and traded heavily the bar comes out wide, and where price passed quickly the bar comes out thin.