Study notes, not signals
Volume Chart Notes is an independent reference on volume charting — the practice of plotting how much of an instrument changed hands and reading that record next to price. It explains the bars, the profiles, and the vocabulary, and it is explicit about where the method stops: description, not prediction.
| Element | What it shows |
|---|---|
| Volume bar | How much traded in one interval |
| Average volume | A baseline of normal activity |
| Relative volume | Activity against its own average |
| Volume profile | Which prices attracted the most trading |
| Point of control | The single most-traded price |
| Value area | The band holding most of the volume |
| Delta | The gap between aggressive buying and selling |
Each column counts how much changed hands during one interval of the chart above it.
On most charts volume sits as a histogram beneath the price panel. Every column belongs to exactly one candle: if the candle spans five minutes, the bar beneath it totals everything traded in those five minutes. The taller the column, the more business was done.
The unit depends on the market — shares for stocks, contracts for futures, coins on crypto venues, and tick counts on many forex platforms, where no central tape exists. The unit changes the scale but not the reading logic: a bar is always a count of activity over time.
Colour is cosmetic. Platforms usually paint the bar green or red to match its candle, which only repeats what the price panel already said. The information lives in the height of the column, not in its paint.
The dates mark published ideas and tools, not endorsements of any method.
A single bar says almost nothing; volume is read relative to what is normal for the same instrument.
The standard move is to overlay an average — often twenty periods — and compare each new bar with that baseline. A bar twice its average marks an unusually active interval; a bar at half the average marks a quiet one. The absolute number matters far less than the ratio.
Context explains most extremes. Opens and closes are mechanically busier, scheduled news concentrates activity into single intervals, and expiry days inflate derivatives volume. An extreme bar with a known cause is evidence of a schedule, not of conviction.
Comparisons across instruments are a dead end. A million shares is routine for one stock and extraordinary for another, so volume only ever speaks about its own chart, against its own history.
A volume profile asks a different question — not when trading happened, but at which prices.
Instead of one column per interval, the profile stacks volume along the price axis. Each interval's activity is distributed across the prices it touched, and the result is a horizontal histogram: long rows where business concentrated, short rows where price passed through quickly.
Three landmarks structure the picture. The point of control is the single most-traded price. The value area is the band containing most of the volume, conventionally near seventy percent. High-volume nodes mark prices where the market lingered; low-volume nodes mark prices it crossed in a hurry.
The vocabulary around profiles is descriptive. Prices that hold volume are said to show acceptance; prices that shed it show rejection. These are labels for what already happened on the chart — useful for talking about structure, silent about what comes next.
Published texts and exchange documentation behind the conventions described here. These are third-party sources: none of them is affiliated with this domain, and nothing here endorses any method as profitable.