Why Volume Bar Colors Can Mislead You█ The Truth Behind Volume Bars — What Do Green and Red Actually Mean?
Most traders learn early on that green volume bars mean bullish activity, and red bars mean bearish pressure. But is it really that simple? What does volume truly reflect, and are we making assumptions that can mislead us?
█ What Volume Actually Is
Volume represents the number of shares/contracts traded during a specific time interval. Every transaction includes both a buyer and a seller. So, volume itself doesn’t distinguish whether a trade was bullish or bearish. Instead, platforms color volume bars based on price movement:
Green: If price closed higher than it opened.
Red: If price closed lower than it opened.
Some platforms, like TradingView, allow you to color volume based on whether the price closed higher or lower than the previous candle’s close.
So YOU, as a trader, have the chance to decide whether to assign volume bars either bullish or bearish! It’s a setting parameter anyone can change. Traders around the globe might look at the same volume bar, but some interpret it as bearish, while others interpret it as bullish. What is the most correct way?
█ The Assumption Behind the Color
This coloring assumes that:
A rising price means buyers were more aggressive (lifting the ask).
A falling price means sellers were more aggressive (hitting the bid).
This is a proxy — an approximation. It simplifies market pressure into a binary outcome: if price goes up, it's bullish volume; if it goes down, it's bearish. But the market isn't always so binary.
However, the assumption is only an approximation of buying vs. selling. In reality, every single trade involves both a buyer and a seller, so volume itself isn’t inherently “buy” or “sell” – what matters is who initiated the trades. As one trading expert explains, talking about “buying volume” vs “selling volume” can be misleading: for every buyer there is a seller, so volume cannot be literally split into purchases and sales. Instead, what traders really mean by “bullish volume” is that buyers were more aggressive (lifting offers) and drove the price up, whereas “bearish volume” means sellers were more aggressive (hitting bids) and drove the price down. The colored volume bar is essentially a proxy for which side won the battle during that bar.
█ Why This Can Mislead You
Price might close higher, not because there were more buyers than sellers (there never are — every trade has both), but because buyers were more urgent. And sometimes price moves due to other forces, like:
Short covering.
Stop-loss runs.
Liquidity vacuums.
This means a green bar might not reflect strong demand, just urgency from the other side closing their positions.
⚪ Example:
Take the well-known GameStop short squeeze as an example. If you looked only at the volume bars during that rally, you’d see a wall of strong green candles and high volume, which might suggest aggressive bullish buying.
However, that interpretation would be misleading.
Under the surface, the surge wasn't driven by fresh bullish conviction — it was massive short covering. Traders who were short were forced to buy back shares to cover their positions, which drove prices even higher. The volume was categorized as bullish, but the true intent behind the move had nothing to do with new buying pressure.
This demonstrates why relying solely on volume color or candle direction can lead to false conclusions about market sentiment.
Does this simple up/down volume labeling truly reflect buying vs. selling pressure? To a degree, yes – it captures the net price outcome, which often corresponds to who was more aggressive. For example, if many buyers are willing to pay higher prices (demand), a bar will likely close up and be colored green, reflecting that buying interest. Conversely, if eager sellers are dumping shares and undercutting each other, price will drop, yielding a red bar that flags selling pressure. Traders often use rising volume on up-moves as confirmation of a bullish trend’s strength, and high volume on down-moves as a warning of distribution, which indeed aligns with traditional analysis
That said, the method has important limitations and nuances, documented both anecdotally and in research:
⚪ Volume is not one-dimensional: Since every trade has both a buyer and seller, one cannot literally count “buy volume” vs “sell volume” without more information. The green/red coloring is a blunt classification based on price direction, not an actual count of buys or sells. It assumes the price change direction is an adequate proxy for the imbalance of buying vs. selling. This is often true in a broad sense, but it’s not a precise measure of order flow.
⚪ Intrabar Dynamics Are Lost: A single bar’s color only tells the end result of that interval, not the story of what happened during the bar. For instance, a 4-hour candle might be red (down) overall, but it could have contained three hours of rally (buying) followed by a steep selloff in the final hour that erased the gains. The volume bar will be colored red due to the net price drop, even though significant buying occurred earlier in the bar. In other words, a large red bar can mask that there were pockets of bullish activity within – the selling just happened to win out by the close of that period. Without looking at smaller time frames or detailed data, one can’t tell from a single color how the buying/selling tug-of-war progressed within the bar.
⚪ Gap Effects and Criteria Choices: The choice of using open vs. close or previous close can alter the interpretation of volume. As discussed, a day with a big gap can be labeled differently under the two methods. Neither is “right” or “wrong” – they just highlight different perspectives (intraday momentum vs. day-over-day change). Traders should be aware that colored volume bars are an approximation. A green volume bar under one method might turn red under the other method for the same bar. This doesn’t mean volume changed – it means the classification scheme changed. For example, a stock that closes below its open but still higher than yesterday will show a red volume bar by the intraday method but would be considered an “up-volume day” in OBV terms (previous close method).
⚪ No Indication of Magnitude or Commitment: A single color also doesn’t convey how much buying or selling pressure there was, only which side won. Two green volume bars might both be green, but one could represent a modest uptick with tepid buying, whereas another could represent an aggressive buying spree – the color alone doesn’t distinguish this (other than one bar likely being taller if volume was higher). Traders often need to consider volume relative to average (e.g. using volume moving averages or looking for volume spikes) to judge the significance of a move, not just the color.
█ Summary
The coloring of volume bars is a visual shortcut, not an exact science. It’s a guess based on price direction — useful, but imperfect. Understanding this helps traders avoid reading too much into what a green or red volume bar actually means.
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