The word imbalance names two different things depending on which school you come from, and that collision confuses a lot of traders. In Smart Money Concepts (SMC), imbalance and fair value gap get used almost interchangeably: a gap between candles that price left behind by moving too fast. In order flow, an imbalance is something else: a lopsidedness measured with real volume, contract by contract, inside the footprint. They share the underlying intuition, that price moved with more aggression than the other side could take, but one infers it from candle shapes and the other one counts it.
What SMC calls an imbalance: the fair value gap
A fair value gap (FVG) is a three-candle pattern. It shows up when the middle candle displaces so hard that the wick of the first candle and the wick of the third never overlap. That unoverlapped space, inside the middle candle’s range, is the gap: a band of prices the market crossed so fast that barely anything traded there.
Example on the NQ: a bullish displacement candle covers the zone between 20,180 and 20,196 in one push. The previous candle’s high stopped at 20,180 and the next candle’s low sits at 20,196. Those 16 points are the fair value gap.
The SMC thesis is that this zone was left poorly auctioned and acts as a magnet: price tends to come back and fill it, fully or partially, before continuing. The school’s typical entries are built on that idea, buying the return into the gap of a bullish displacement on the argument that the same money that opened the move will take control there again.
Note the important detail: marking an FVG requires nothing but candles. No volume-at-price data, no knowledge of who executed against whom. It’s a read based on shape, available on any chart, including spot forex with no centralized volume at all.
What an imbalance is in order flow
In the footprint, an imbalance is a concrete measurement: you compare, diagonally, the volume executed at the ask on one level against the volume executed at the bid on the level below, and when one side exceeds the other beyond a threshold (the industry standard is a 300% or 400% ratio), there’s real aggression lopsidedness at that spot. The guide to order flow imbalances covers the calculation, the thresholds and the filters. Here the idea is enough: it’s a figure measured on actual executions, not an inference drawn from candle silhouettes.
That difference in raw material changes everything. The FVG says “price ran through here fast, aggression was probably one-sided.” The footprint imbalance says “at this level, 480 contracts were bought aggressively against 110 sold.” One is a reasonable hypothesis. The other is a count.
The same candle, seen by both schools
The two reads usually point at the same spot, which is exactly why they get conflated. The displacement candle that leaves an FVG is, almost always, a candle loaded with aggression in the footprint: a swollen delta and imbalances printed across several levels.
Where the schools part ways is in what you can do afterwards. With candles alone, the FVG gets marked and you wait for the return with a fixed rule. With a footprint, when price comes back into the gap you can watch live whether that return is being bought, sold or absorbed. The zone is the same. The information on arrival is not.
| Fair value gap (SMC) | Imbalance (order flow) | |
|---|---|---|
| What it compares | Wicks of three consecutive candles | Ask vs bid volume, diagonally |
| Data required | Price only (candles) | Executed volume per level (footprint) |
| Threshold | None: the gap exists or it doesn’t | A ratio, typically 300% or 400% |
| What it claims | Price ran through without trading | One side executed several times more |
| Nature | Inference from shape | Measurement on executions |
How they combine: the gap marks the zone, the footprint decides
My preferred way to trade this uses both. The FVG (or any fast-move zone, which on a volume profile shows up as a low volume node) hands you an area of interest ahead of time. The footprint tells you what to do when price gets there.
Continuing the example: hours later the NQ pulls back and enters the gap from 20,196 downward. At 20,184, inside the zone, the selling starts to dry up and the footprint prints a buy imbalance: 480 contracts at the ask against 110 at the bid on the level below, above 400%.
That division of labor is the one that works: the zone can be anticipated with the gap, but the decision to enter belongs to the flow. If instead of buy imbalances the return into the gap shows aggressive selling cutting through with no reaction, the FVG has failed as a zone and the footprint tells you before your stop does. It’s the same hierarchy I use with stacked imbalances: the level proposes and the execution confirms.
Which one should you use
It depends on your data and your market, and it pays to be specific:
- If you trade candles with no volume-at-price (spot forex, stocks on basic data, any TradingView chart without a footprint), the FVG is a reasonable way to map fast-move zones. It’s the data-poor version of the same idea, and as a map it does its job.
- If you have a footprint on a centralized market (futures like the ES and NQ, or exchange-traded crypto), the measured imbalance is information of a different grade. Keep marking the gaps if you like, but decide with the real aggression count instead of the silhouette of three candles.
- If you come from SMC and are making the jump, the bridge is direct: the concepts you already use (displacement, untraded zones, the return to the gap) have measurable counterparts in the footprint and the delta. The full route is laid out in the footprint chart guide and in moving from indicators to order flow.
What I don’t recommend is trading FVGs blind on futures while a footprint is available to you. Giving up the view of actual executions when it’s sitting in front of you means choosing the inference over the data.
Frequently Asked Questions
Are a fair value gap and an imbalance the same thing?
No. A fair value gap is a three-candle pattern marking an unoverlapped band of prices, detected on the candle chart alone. An order flow imbalance is a measured lopsidedness in the footprint, comparing ask and bid volume diagonally against a threshold. SMC uses the word imbalance for the former, and that’s where the confusion comes from.
Does a fair value gap imply there were imbalances in the footprint?
Almost always the displacement candle that leaves the gap comes loaded with aggression and prints measured imbalances across several levels. But it’s not automatic: gaps can appear in thin, low-participation moves. The advantage of the footprint is that you don’t assume it, you check it.
Can I trade fair value gaps without a footprint?
Yes, and in markets without centralized volume, like spot forex, it’s one of the few ways to approximate zones of one-sided movement. The limitation is that when price returns to the gap you can’t see whether the zone is being defended or run through: that read requires volume per level.
What do I need to measure real imbalances?
A market with centralized volume (futures or exchange-traded crypto), tick data, and a platform with a footprint that compares bid and ask per level, such as ClusterDelta or others in the space. With that, the imbalance stops being a visual inference and becomes a ratio computed on real executions.