Standard volume charts show when trading occurred by plotting volume across time.
A Volume Profile shows where trading occurred by stacking volume at each price level.
Point of Control
The longest bar on the profile is the Point of Control (POC), the single price level where the highest volume traded. This level is watched closely because it often acts as a magnet for price.
Value Area
Surrounding the POC is the Value Area, which is the price range that contains roughly 70% of the total volume. Prices inside the Value Area are considered "fair" or accepted by the market; prices outside it are seen as relatively expensive or cheap.
How Traders Use It
Traders use the profile to identify high-volume shelves that can act as support or resistance, to see whether price is currently inside or outside the Value Area, and to judge whether the market is balanced (heavy volume concentrated in a tight range) or trending (volume spreading out across a wider range of prices).
Tool Glossary
The Basics
Candle (OHLC)
One bar of price data: the open, high, low and close. This tool uses the high, the low and the volume. When a session's range covers more than one price level, the volume is split across those levels by how much of the range falls in each one. The open and close do not decide where the volume is stacked.
Session
One trading day. Time in this tool is measured in sessions rather than calendar days, so weekends and holidays are skipped.
The Patterns
Volume Profile
Volume stacked by price instead of by time. A standard volume chart shows when trading happened. This tool turns it sideways to show where.
Point of Control (POC)
The single price level that traded the most volume on the profile. It is the longest bar, and price often returns to it.
Value Area (VAH / VAL)
The price band that holds 70% of the volume, starting at the POC and expanding into the heavier neighboring level until it reaches that 70%. The top is the Value Area High. The bottom is the Value Area Low. Price inside the band is trading where most volume was done. Price outside it has moved beyond that.
Volume Shelf
A price level that traded heavy volume and more than the levels on either side of it. Above price it tends to act as resistance. Below price it tends to act as support.
Trading
Support and Resistance
Price levels where buying or selling has shown up before. This tool treats high-volume shelves that way: a shelf above price as resistance, a shelf below price as support.