Volume: the second half of every candle

Price says what happened. Volume says how much conviction was behind it.

Volume is the number of units traded in a period. On its own it is meaningless; read alongside price it becomes one of the few genuinely useful confirmations available for free.

The four combinations

Where volume matters most

1. Breakouts. A break of a level on thin volume is the classic false breakout. The same break on heavy volume has participation behind it.
2. Reversals. A large spike of volume after a long trend, with price rejecting sharply, often marks exhaustion.
3. Ranges. Volume drying up inside a range means a decision is approaching, though it says nothing about the direction.

Volume versus open interest

On futures these two answer different questions. Volume counts activity; open interest counts positions still held. High volume with flat open interest means positions changed hands. High volume with rising open interest means new money entered. The second is a stronger signal.

Reading volume at the level that matters

Volume is most informative at three specific places on a chart, and largely noise everywhere else. Learning to look only at those three saves a great deal of confusion.

At a level being tested. When price returns to a previous high or low, the volume on that test tells you whether participants are defending it. Heavy volume with price rejecting means real sellers are present. Light volume drifting into the level usually means it will break, because nobody is there to stop it.

At the moment of a break. This is the classic use. A level broken on volume noticeably above the recent average has participation behind it. The same break on volume below average is the definition of a false breakout, and it is how most breakout traders lose money — they take the signal without checking whether anyone came with them.

At the end of a long move. A sudden volume spike far above anything recent, with a long wick and a close back inside the range, is the signature of exhaustion. Someone large was filled, and the direction that produced the move has run out of participants.

Volume profile, in plain terms

Standard volume bars show how much traded in each period of time. Volume profile shows how much traded at each price instead — a horizontal histogram running up the side of the chart.

The distinction matters because markets return to prices where a lot of business was done. High-volume areas act like magnets and tend to slow price down; low-volume areas are travelled through quickly because nobody is defending them. If you understand nothing else about volume profile, understand this: price moves fast through thin areas and gets stuck in thick ones.

You can approximate the same idea without any special tool. Look for the price bands where the chart spent the most time over the last few weeks. Those are your thick areas. The zones price passed through in a single candle are the thin ones.

Why crypto volume is harder to trust

In regulated equity markets, reported volume is audited. In crypto it frequently is not, and the difference matters.

• Wash trading. The same party buys and sells with themselves to inflate reported activity, making a venue look more liquid than it is. This has been documented repeatedly on smaller exchanges.
• Fragmentation. The same asset trades on dozens of venues. Volume on one exchange is not the market's volume.
• Incentive programmes. Some venues pay traders to generate volume, which produces activity with no informational content whatsoever.

Two defences work. First, cross-check against order book depth, which is far harder to fake than a volume number — a venue claiming enormous volume with a thin book is telling you something. Second, prefer the venues that dominate real volume; the exchange volume panel ranks them.

Volume in different market conditions

In a healthy trend, volume expands on moves in the trend direction and contracts on pullbacks. That pattern is what confirms a trend is intact. When pullbacks start arriving on heavy volume instead, the character of the market is changing.

In a range, volume typically dries up as the range matures. Traders lose interest, spreads widen, and the market coils. The eventual break out of that range usually arrives with a sharp volume expansion — which is the confirmation that it is real.

In a capitulation, volume goes vertical. Everyone who was going to sell does so at once. These moments are terrifying to live through and frequently mark local lows, because after forced selling exhausts itself there is nobody left to sell.

Common questions

Does high volume mean price will go up?

No. Volume has no direction of its own — it measures participation, not intent. High volume on a falling candle means conviction among sellers just as much as high volume on a rising candle means conviction among buyers. Always read volume together with what price did.

What counts as high volume?

It is entirely relative to that market's own recent history. A figure that is enormous for a small-cap token is nothing for Bitcoin. Compare each candle's volume against the average of the last twenty or so candles on the same timeframe, never against another asset.

Is volume useful on very low timeframes?

Less than people hope. On one-minute and five-minute charts, volume is dominated by market-making and automated flow that carries little information about direction. It becomes considerably more meaningful from the hourly timeframe upward.